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Arrggg, I can't take much more of this SST trans

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Posted by: JES_LS

I really have to get some serious time and 'cookie jar' funds going on, because this crappy SST transmission is really getting to me.

Just in the last day, I have had some seriously annoying and dangerous behavior.

First the trans is shuddering when I have to transition from a crawl (at the point where the trans is about to downshift from 4th/5th to 2nd) to accelerating at any appreciable level. I'm not getting any "E" on the dash, but there is a lot of roughness, noise and indecision in the transmission. The local transmission shop Mgr just listened to my complaint and said that I need to bring it in for a 'complete' Flush-n-fill and then a reset of the computer. Of course I heard him say that to three other customers while I waited to talk to him.

second what is with the crappy downshift logic, I mean I'm rolling down a highway ramp in third and pull back for a downshift. There is no immediate response, so I just forget the downshift and turn my attention back to driving.
More than one heartbeat later, the transmission goes from third to freewheeling and lets the motor just about drop to idle speed. Then another heartbeat goes by before the transmission engages 2nd gear, at that point the motor has to violently rev from near idle to about mid tach and the car lurches like I missed a gear downshifting my motorcycle. It can be so violent that the Stabilitrac will engage for several seconds to try to supress the lurch.

I mean the rest of the crap that this trans is programmed to do I can barely stand, but if this is how a 40,000 mile sst behaves then the trans swap has to occur this fall.

Posted by: HyeLifeLS

I think your have solenoid pack and valve cover problem. I had lots of problems with my tranny too. Had to change those damn things twice, ran me over $2000.

Posted by: beaups

well my behavior was similar and my tranny did fail. however the replacement tranny acts the same way. I found a bunch of oil in the cylinder wells. changed vc gaskets. coils arrive this week. I'm really thinking that the car is missing bad enough that it's not producing the amount of power that it "thinks" it's producing. what I mean is scan shows engine load very high and I think it really screws up all the shift points and patterns. I'll let you know what I find out but I have also heard others complain of coils wreaking havoc on trans behavior.

Posted by: LS4me

Remember, in SST the trans won't down or upshift. It will stay in the selected gear. If you're too fast for the gear, you will bump off the rev limiter. If you come to a stop in 4th or 5th, the trans will shift to 2nd as soon as you get close to a full stop. The trans has a "dead" spot in 4th and 5th around (IIRC) 5mph. You're lugging the engine and the trans doesn't really know what to do. Remember, you won't get any kind of automatic shift while in SST mode.

The logic won't let you over-rev the engine, so your 3-2 shift won't happen until the computer figures the engine is at a "safe" rpm.

If I read your post correctly, it sounds like this is your problem.

Posted by: JES_LS

Quote:

Originally Posted by LS4me

Remember, in SST the trans won't down or upshift. It will stay in the selected gear. If you're too fast for the gear, you will bump off the rev limiter. If you come to a stop in 4th or 5th, the trans will shift to 2nd as soon as you get close to a full stop. The trans has a "dead" spot in 4th and 5th around (IIRC) 5mph. You're lugging the engine and the trans doesn't really know what to do. Remember, you won't get any kind of automatic shift while in SST mode.

The logic won't let you over-rev the engine, so your 3-2 shift won't happen until the computer figures the engine is at a "safe" rpm.

If I read your post correctly, it sounds like this is your problem.

Well, I do understand how the transmission functions and while I do not like many of the so called features, but this delayed, slow to shift and violent lurch is something new.

So is the hesitation when its needs to downshift from crawling along in 4th or 5th because I suddenly have the need to accelerate instead of comming to a stop.

It is interesting that several people have posted here and emailed me that I need to change my coils and plugs. Can anyone better explain this connection between the ignition coils begining to fail and the transmission logic getting screwed up????

Posted by: Mac98SHO

Because hesitation is usually the ignition or fuel system, not a tranny.

These, type of coils can fail in stages or all at once. I have experienced both. So honestly the cheaper fix is the coils. This can possible fix your problem.

Hesitation will really screw with tranny shifting.. since the PCM controls the tranny. It did in my SHO, but I imagine more so in this car. It has been my experience if tranny is going to fail it fails... rarely give any warning. Unless it th Torgue converter (another subject)

For example when accelrate in my SHO if I am in the fuel hard and left off suddley, my PCM and shift the tranny and rock my car.... PCM looking fo WOT and it doesnt have it..... thus the little PCM glitch or screw up.

So imagine your coils are failing and the PCM looking to shift at certian RPM based on speed TPS postion and air flow, but your car performance is lacking the PCM will shift the tranny and thinking normal then compensate.... thus some crazy shift patterns.

Now I might be wrong or myabe over simplifing this, but I hope this help you understand why we say check coils. Besides it the cheaper fix.

Good luck

Posted by: Pete02LSE

Interesting post...as I posted something about my SST shifting screwy. I too had a hesitation and a known high RPM misfire.

So...today, I replaced 4 of my coils (the entire passenger side) with new Borg-Warner replacements. I can tell you this...the car definitely idles smoother and accelerates smoother...and from what I could tell from my 15 minute test drive, the high RPM misfire is gone. Zero surging...and...it pulls hard up to redline. However...the bad news is...the SST is still wacked. In SST, from a dead stop to WOT...it still feels like it slams into a brick wall. In D4 or D5, from a dead stop to WOT, it pulls like a freight train. I only hit 80 on a 4 lane near my house and it was definitely pull strong when I backed out of it.

My next step is to replace the driver side coils and see what that does for me. At the same time, I figured I'd disconnect the battery cable and reset the PCM...just to see what that will do.

Does anyone have a diagram of where the solenoid pack is located? Is it internal to the tranny? Hopefully it is not a dealer-only servicable item.

Oh...and if the SST stays hosed, at least we should see better mileage with the coils firing properly.

Thanks,
-Pete
02LSE

Posted by: JES_LS

Well I'll look into replacing the coils, but the pcm doesn't show a single misfire code.
Are there any good aftermarket brands of coils for the LS, I know the newest mustangs are starting to make the market produce HD coils for the coil on plug motors.

Posted by: Pete02LSE

Quote:

Originally Posted by JES_LS

Well I'll look into replacing the coils, but the pcm doesn't show a single misfire code.
Are there any good aftermarket brands of coils for the LS, I know the newest mustangs are starting to make the market produce HD coils for the coil on plug motors.

See...that's the odd thing about our LS...it never threw a code either. There was a definite high RPM misfire that you could hear in the exhaust note (dynomax ultra-flo mufflers). Also, it was getting to the point that it would surge under WOT and you could feel the misfire.

To compare...when I ran a top end engine cleaner through my Camaro SS, it caused a misfire and you could feel it...and...as expected...it threw a code. Why the LS won't is beyond me. Sorta makes me wonder how liberal the PCM is with throwing a code.

Anyway...to your question about coils. I found mine at O'Reilly autoparts and they are Borg-Warner. They sell for $37.99 ea. Which...is far cheaper than any other coil I have found. I'll be able to replace all 8 for about $322. a fraction of the cost of the Ford ones. I figure Borg-Warner is a reputable brand for other parts...as for coils...I dunno...but...I'm willing to try them.

-Pete
02LSE

Posted by: JES_LS

Thanks pete, I was just comparing it to my GT's pcm which will trap a code at the drop of hat, but not turn on the MIL.

but three scan tools have not found anything wrong with anything, so I guess I'll have to invest in the coils.

Thanks for directing me to the BW coils, I might just try to get them done in the next week before I take the car on the family vacation.

I'll spend some time later today looking for HD coils.

does anyone know if the coils are the same as the ones in the 05-06 mustangs?

If this and a computer reset doesn't cure the shifting crap, then I'll be taking it off the road in sept to swap the trans.

Posted by: beaups

to replace solenoid pack you pull the trans fluid pan then it's up in the bottom of the trans. you don't have to drop the trans but it is a messy job. what year is your ls? if it's 03 or newer with the electronic throttle that makes things even more interesting as the computer screws with the throttle A LOT during normal acceleration/shifts.

Posted by: JES_LS

well mine is an 02 and I'm not going to spend my time wrenching in that trans, if it is broke then its gone. It's been a pain in my posterior since we bought the car. I just don't like it (like every other automatic I have ever owned).

as for the coils, I found some good pricing on motorcraft coils but I'm confused.
one site says that the 02 - 05 v6's use a dg-517, but another says that the 00-03's use a dg-497. Motorcraft's own site catalog only lists the 02-05 coils as dg-517, but the parts cross reference lists both of them for the long ford number.

what is the difference between the dg-497 and dg-517 coils?

Posted by: Pete02LSE

Sorry JES_LS...I don't know the difference in the coils.

More good news about my coil swap though. Today, my wife drove the car about 100 miles and it hit 19.6 mpg. That has NEVER happened in our LS. So...I went ahead and ordered 4 more coils. As I mentioned before...even if it does not fix my trans problem...the car should get much better gas mileage.

It's hard to believe that the original coils took a crap at ~50k. I have 75k on my Camaro and it shares the coil on plug design and has NEVER had a problem with them.

-Pete
02LSE

Posted by: JES_LS

Well I'm glad something seems to be helping you.
Twice today the LS did the:
call for a downshift at a safe speed,Get nothing, then the trans shifts out of gear to a neutral, then it coasts for a heartbeat as the engine drops to idle, then it slams down into the lower gear hard enough to break both rear tires loose. stabilitrack light flickers for serveral seconds, then everything seems to return to normal.
the only difference was this time it did once going from fourth down to third and then much later in the day going from third down to second.

Something is very not right with this, so I think I had better order the coils and the clutch pedal assembly tomorrow.

Posted by: LS4me

Quote:

Originally Posted by JES_LS

Well I'm glad something seems to be helping you.
Twice today the LS did the:
call for a downshift at a safe speed,Get nothing, then the trans shifts out of gear to a neutral, then it coasts for a heartbeat as the engine drops to idle, then it slams down into the lower gear hard enough to break both rear tires loose. stabilitrack light flickers for serveral seconds, then everything seems to return to normal.
the only difference was this time it did once going from fourth down to third and then much later in the day going from third down to second.

Something is very not right with this, so I think I had better order the coils and the clutch pedal assembly tomorrow.

Sounds like the solenoid pack.

Posted by: JES_LS

Quote:

Originally Posted by LS4me

Sounds like the solenoid pack.

Great, can you give me a part number on the pack so I can price it out?
and after I drop the pan will I have and gaskets that I need to replace?
There is no way I'm taking the car to the dealer or going to them for parts (I like the little bit money I earn)

And how long will this new solenoid pack last 20K, 30K, 40K miles, or is this some new miraculously improved and never fails again repair (like the plastic intakes on my mustang gt).

I'm not going to just keep repairing transmission, I really don't like it well enough!

Posted by: 2002_LS_V8

i dont have the SST tranny and i never have any problems.. i guess im lucky because it didnt come with it?? altho i would like to play with it

Posted by: mholhut

My tranny behaves the same way as far as downshifting... I just call it the nature of the beast. Going from 3rd to 2nd at 35 mph will chirp the tires... not a good thing... when downshifting, I always looked at the tranny as a 4 speed > 5th was 4th, 4th was 3rd, etc.

I'd start with some simple things... have the coils balance load tested at a stealership... when the engine is warmed up, this test can see which coils have more or less resistence and they'll recommend replacing the coils with higher resistence... I think.

Next step up from that is having the tranny reflashed. I thought there was a software update a long time ago and I think it's a pretty reasonable cost... hours labor maybe. people have reported positively about it's effects.

After that, time to tinker with the tranny.

Man, that just doesn't sound right.

Posted by: JES_LS

Quote:

Originally Posted by mholhut

My tranny behaves the same way as far as downshifting... I just call it the nature of the beast. Going from 3rd to 2nd at 35 mph will chirp the tires... not a good thing... when downshifting, I always looked at the tranny as a 4 speed > 5th was 4th, 4th was 3rd, etc.

Well the whole functional logic of the these downshifts is wrong. The violent engagement after letting the engine revs drop that much is totaly backwards and since the computer controls the timing, the speed and slippage of the shift it is inexcusable. It would not take of a change in the logic to fix the shifting issue. That is if it is not caused by the coils.

Quote:

Originally Posted by mholhut

I'd start with some simple things... have the coils balance load tested at a stealership... when the engine is warmed up, this test can see which coils have more or less resistence and they'll recommend replacing the coils with higher resistence... I think.

Well since my car's never see the dealership (cue background music,... Billy Joel's "Its a matter of trust"), I don't have a way to load test the coils, besides if one is cooked then the others can't be far behind and I'm not going to keep changing them. I'm going to replace the coils, its just a matter of king and when..

Quote:

Originally Posted by mholhut

Next step up from that is having the tranny reflashed. I thought there was a software update a long time ago and I think it's a pretty reasonable cost... hours labor maybe. people have reported positively about it's effects.

Unless there was another reflash since dec 2004, I already have the latest flash for the 2002 v6. I made the dealership I bought the car from do the reflash before I would take the car back home (I bought out my Father-In-Laws lease). Great deal, but now the transmission has come back to bite me one. That's the second time I've bought out one of his leases and had it bite me (don't ask about the 93 tracer my wife HAD to buy).

Quote:

Originally Posted by mholhut

After that, time to tinker with the tranny.

Okay to me that means rip it out and install that manual I have on the garage floor.

Quote:

Originally Posted by mholhut

Man, that just doesn't sound right.

LOL, leave my sexual preferences (or lack thereof) out of this. JK

Posted by: LS4me

Quote:

Originally Posted by JES_LS

I did it about a year and 20K miles ago. So far so good. The old part was a French made part. The new one is from Bosch. The part number is xw4z-7g391-ac. Bill Jenkins has it for ~$189 at www.teamfordlv.com. Here's the link: http://www.trademotion.com/partlocat...&siteid=214270

Posted by: JES_LS

Well lets see I do about 20K mi a year in the Lincoln, so according to your results so far it will be good until next year.

Does anybody out there that has replace the solenoid pack gotten a lot of miles on the new part??

Posted by: JES_LS

Quote:

Originally Posted by LS4me

Thanks for the tip, they do seem to be the cheapest

Posted by: HyeLifeLS

If you replace the solenoid pack, make sure to replace the valve cover as well (sorry no part numbers). The dealer changed my solenoid pack at about 60,000 miles and then at about 74,000 the same problems came back. Than they changed the valve cover and the solenoid pack again. Now I am on 113,000 and no tranny problems yet (knock on the wood).

Posted by: SoonerLS

Quote:

Originally Posted by HyeLifeLS

If you replace the solenoid pack, make sure to replace the valve cover as well (sorry no part numbers).

I think you mean valve body, not valve cover.

Posted by: JES_LS

well if I have to replace the valve body does any one here have the part number for it.

then I can price it out

Posted by: TheRebel

The valve body for an 02 with a 5R55N is part number 7A100.

Posted by: JES_LS

Quote:

Originally Posted by TheRebel

The valve body for an 02 with a 5R55N is part number 7A100.

can I ask were did you get that number.
It did not look right to me and when I tried to plug it into my three online part number search tools, none of them new what to do with it either.

I was expecting a number like YW4Z2455BA which is the clutch pedal assembly support braket.

does anyone else have a number for the valve body.

Posted by: TheRebel

It looked funky to me too. I got it out of a service manual. The manual prolly doesn't give the correct number to order, but you might be able to call Ford and see if they can cross it to a catalog number you can order.

Posted by: LS4me

Quote:

Originally Posted by JES_LS

Call Bill Jenkins at www.teamfordlv.com. He will be able to hook you up with a good price as well as the part number.

BTW, how do you know you need a new valve body? Sounds to me like you're just replacing parts trying to chase down a problem. A diognostic fee is much less expensive than just throwing parts at an unknown issue.

Posted by: JES_LS

I haven't replaced anything yet, and the $198 bucks that the dealer near me wants to hold my car all day and then spend twenty minutes taking their half-assed guess is $ I could put to coils or the solenoid pack.

I'm just trying to get prices while I continue to gather information.

I would rather know that the problem is the ignition coils and just be done with it.
or I'd rather know that parts cost of repairing the sst is some XX% of the cost of parts for the Swap the MTX in project (and once it passes about 70%, I will do the swap instead).

Posted by: LS4me

Quote:

Originally Posted by JES_LS

I haven't replaced anything yet, and the $198 bucks that the dealer near me wants to hold my car all day and then spend twenty minutes taking their half-assed guess is $ I could put to coils or the solenoid pack.

I'm just trying to get prices while I continue to gather information.

I would rather know that the problem is the ignition coils and just be done with it.
or I'd rather know that parts cost of repairing the sst is some XX% of the cost of parts for the Swap the MTX in project (and once it passes about 70%, I will do the swap instead).

Just to clarify, there is no difference between the "SST trans" and the "non-SST trans". The transmission is the same, just the shifter is different.

Posted by: JES_LS

Quote:

Originally Posted by LS4me

Just to clarify, there is no difference between the "SST trans" and the "non-SST trans". The transmission is the same, just the shifter is different.

no disrespect, but I believe you are wrong. First of all I was not talking about changing the car from an SST trans to Non-SST trans, I was talking about swapping my 2002 SST transmission for a 2002 Factory Manual Tranmission. After all it was available in the V6 cars, which is what I have.
Also while the guts of the 5r55n transmission is the same between cars the logic that is involved is not, at some level I am sure that it is this logic (or sometimes lack of) that contributes to the fraility of the SST trans.

My upset is great for these three reasons.
1. It is a problem with the very program that is supposed to protect the transmission and the remainder of the driveline. Ironic that a crude 1960's automatic with no electronic controls can protect itself and rest of the car better than the nice new modern design in this instance.
2. It is this self-preserving logic that causes more damage to the entire car then merely ignoring the driver's command or simply having better logic as to how the shift should be acomplished.
3. The fact that the processor for the transmission can be reprogrammed with a dealership level tool, but no tuner has stepped up to fix this serious gap in the cars capabilities. This is the thing that I find most annoying.
4. All the issues I have with the SST's behavior could be corrected with proper programming, which as an IT professional just makes it all the more frustrating.

I'd be more than happy to discuss what is really wrong with the design of this transmission in another thread or privately.

right now on this thread I'm trying to get all the info I can to price and diagnose the issue with my LS, so that when it completely fails or I get the kids back in school, I can do whatever I deem the best cost/risk wise

Posted by: beaups

nope. sst and non sst are IDENTICAL. only difference is the shifter. People w/base models (no sst) simply replace the shifter w/an SST one and voila "SST TRANSMISSION".

Posted by: LS4me

Quote:

Originally Posted by beaups

nope. sst and non sst are IDENTICAL. only difference is the shifter. People w/base models (no sst) simply replace the shifter w/an SST one and voila "SST TRANSMISSION".

Quote:

no tuner has stepped up to fix this serious gap in the cars capabilities

is because, believe it or not, every car's pcm is unique. By that I mean each pcm stores information in a different place. That's why a chip won't work and a tuner needs to know the specific calibration for each LS. The sport calibration I mentioned above isn't the pcm calibration assigned to my car. Should I go to the dealer with a calibration issue, I could be in trouble. The LS' electronic control is very sophisticated. Everything from the power windows to the radio to the transmission is connected electricly.

Posted by: JES_LS

Quote:

Originally Posted by LS4me

Like I did 3 or 4 years ago!! I know of at least a half dozen others that have done this. Reprogram the pcm with a sport calibration and I even have D4!

There has been talk of a manual/auto swap. There will be problems. The PCM for one. Then you have to purchase the pedal assembly. It would be less expensive to just buy a manual LS.

If you're talking V8, the Getrag can't handle the torque and won't last very long. Remember you could only get a manual Taurus SHO for quite some time because the auto couldn't handle the Yamaha's torque? Same thing here, only backwards.

Do yourself a favor and research the past threads on the pcm programming. One reason that is because, believe it or not, every car's pcm is unique. By that I mean each pcm stores information in a different place. That's why a chip won't work and a tuner needs to know the specific calibration for each LS. The sport calibration I mentioned above isn't the pcm calibration assigned to my car. Should I go to the dealer with a calibration issue, I could be in trouble. The LS' electronic control is very sophisticated. Everything from the power windows to the radio to the transmission is connected electricly.

I understand that every pcm is different, but if Torrie can find the Trans programming in an LS calibration, then He can disable it for a manual. In fact I even emailed Torrie before and he seemed certain at the time that he could customize my PCM for non automatic operation.

as for the pedal assembly and the other hard parts, they are factory parts it is not like the LS was never designed to have any manual trans.
The Getrag will do in either car for starters. If I cannot upgrade it, there are other transmissions that can be sourced. I mean I know that in europe is possible to find a manual transmission for the xkr jag coupes, which use the 3.9(4.0 now 4.2) motor and could probably be sorted out.

It can all be done, it just depends on how badly you want it.
After some of the other swaps I have done in the past, this one is do able. The pcm is the hardest for the V6 and with Torrie involved this seems to be a non-issue.
the V8 will be much more mechanically challenging, but I pretty confident it can be done (not with the stock getrag). No scratch that it can be done, its is only a matter of time.

anyone who wants a list of the crazy swaps I have put together in the past is welcome to PM or email me.

Posted by: SoonerLS

Quote:

Originally Posted by LS4me

If you're talking V8, the Getrag can't handle the torque and won't last very long. Remember you could only get a manual Taurus SHO for quite some time because the auto couldn't handle the Yamaha's torque? Same thing here, only backwards.

Actually, the 3.0L SHO V6 didn't produce enough low-end torque for an ATX to function properly. That's why the ATXes all had the "stroker" 3.2L SHO; it increased the low-end torque specifically for ATX operation.

Posted by: Fla02LS

I have got lost reading this thread. You have a 2002 V6 with SST? Didnt think that was an option. I too had a 2002 V6 that was ridiculous with its shifting. Do you have a modified intake? Mine started acting up after i modified the airbox. Even my '05 V8 after i removed the snorkel thing off the stock airbox it immediatly acted different not to mention sounding like an old carburated 350.

Posted by: JES_LS

Quote:

Originally Posted by Fla02LS

I have got lost reading this thread. You have a 2002 V6 with SST? Didnt think that was an option. I too had a 2002 V6 that was ridiculous with its shifting. Do you have a modified intake? Mine started acting up after i modified the airbox. Even my '05 V8 after i removed the snorkel thing off the stock airbox it immediatly acted different not to mention sounding like an old carburated 350.

Yes, I have a 2002 ls sport v6 with sst.
no, I have not modified the airbox except to add a two part washable filter.

Posted by: JES_LS

well I tonight I picked up my wife to drive her home from work.
I pulled into the lot, and since she was going to be a few minutes I cut the engine to sit and wait.

when she came out the ls started, but was shuddering at idle. I goosed the gas and it shudder with what felt like a minor miss and then cleared out.

So I guess I really have to move on the coils soon.

Posted by: Fla02LS

I thought the coils and such were a V8 problem. My 2002 V6 had 87k miles and it ran great.

Posted by: JES_LS

Quote:

Originally Posted by Fla02LS

I thought the coils and such were a V8 problem. My 2002 V6 had 87k miles and it ran great.

nope, it did it agian tonight, even shuddering at a couple of stoplights.

Posted by: Fla02LS

Have you explored the thought of the MAF sensor?

Posted by: SoonerLS

I'm fairly certain that I've read about V6 owners having to have their coils replaced, but it does seem to be more prevalent in the V8s. The coils on the V8 and V6 are the same, IIRC, so there's no reason that the V6es couldn't have the same problem. I think the valve cover gasket leak that often leads to the premature death of the coils predominantly affects the pre-'03 V8s, but that's not the only thing that can kill the coils.

Posted by: JES_LS

well according to several sources the v8 coils and the v6 coils have different numbers Motorcraft catalog lists v8- dg515 and v6 - dg517 or dg497(which no one seems to be able to confirm).
Anyway if they are the same coils then we all share the same crap.
I'm figuring that this miss will get bad enough in a couple of weeks that I'll actually have a code thrown to tell me which one is the problem. As it is now there is no code in pcm.

Odd since my mustang throws a misfire code at the drop of a hat, even when it can't tell which pair of cylinders is having the problem (4 pack coils).

I would have thought that our LS's PCMs would be more sensitive to misfires, not less