5R55 Tranny Servo Bore Fix

RCodePaul

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Found this on another site-
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All kidding aside, the 5R transmissions aren't all that bad but if you plan on diag-ing one you best read up on some of their idiosyncrasies and operating strategies. Now, I don't work on these little guy transmissions that much (SuperDuty is the flavour out here) but I do recall (recall is a dangerous word for an old man to use) some concerns with valve body gaskets. Now..... I also recall that the gaskets are bonded to the separator plate so it will be up to you to be very careful in any disassembly. The possibility for debris in a spool is real....

However, the 5R55 is fairly well known for wearing the servo bores... Bear in mind that the 1-2 shift has a band apply for 2nd gear.... This will have to be checked at the same time that you have the main control out. You're in luck here because there is a repair available that will keep you from replacing the trans case if the bores are pooched.
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Anybody aware of the servo bore fix? I've been told locally the cases typically need machine work done to "un pooch" the bores. Hoping there's a bore liner kit of some sort.
 
servo bore dot com

IF anybody makes that it would be Sonnax Poke around there a little you may find a part# and instructions.

Thanks. There is a parts list there that refers to a "Servo Fix" kit that they don't sell. Googled that verbiage and I guess it's pretty common. At the servobore site there's a copy blurb that reads

Apply oil for both the Overdrive and Intermediate servos on Ford's 5R55W, 5R55S, and 5R55N type transmissions comes up through the servo pin bore and through the hollow pin, applying the servo. This requires the pin to seal in the servo pin bore, as does the release oil used by both servos. As time goes by and the servos go through many apply and release cycles, the case wears and the pin no longer seals. This is especially true of the Overdrive servo, which is used for second gear as well as fifth. This means that the servo cycles twice every time the vehicle takes off from a stop and achieves cruising speed. This wear causes both the apply and release oil to leak, dumping pressure. With these pressure loses, the servo both lacks adequate pressure to either hold the band completely applied or release it quick enough to avoid burning it.
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Sounds awfully familiar.

For some of you the best copy on the site is found in describing using the reamer. "Lubrication plays a big part in proper bore reaming. Using improper or inadequate lubrication will lead to over-sized bores and excess aluminum build ups on the reamers."
and the king of all quotes-
"I personally use my stone on my reamers every time I use my tool."
 
Repair Kit on eBay

Huh, weird so few (none other than me) here have had this problem when my indy says this is a common issue. So common that there has been a kit developed to repair it.

A line from the eBay listing, "These transmissions will wear out the case inside of 80,000 miles. Period. So it's either this or a new case."

Not exactly obviously...

http://cgi.ebay.com/ebaymotors/5RW-...t=Motors_Automotive_Tools&hash=item414a9ec2be
 
I think most times when the tranny gets wacky, it just goes in for a rebuild. Hopefully the builder knows about the weak bore and just sleeves it without ceremony.
The only common DIY thing discussed here is the solenoid block. A few people have gone after the valve body and converter.

And you do know that the entire case would have to be cleaned after sleeving the bore, right? (just checking) The "machine work" referenced is probably reaming the bore and driving in the sleeve.
 
Yup yup.

I think most times when the tranny gets wacky, it just goes in for a rebuild. Hopefully the builder knows about the weak bore and just sleeves it without ceremony.
And you do know that the entire case would have to be cleaned after sleeving the bore, right? (just checking) The "machine work" referenced is probably reaming the bore and driving in the sleeve.

Yeah, thanks. Now after reading up a bit and seeing the pics on the rebuilder site, I see what the machine work is.
Of course that's an R&R deal, I get that.
Sounds like the place I went doesn't have the reaming kit, rather they send the case out to a machine shop which uses a mill. Seems common enough (except around here) that he mentioned it as a possible cause of the issues.
When they were referring to worn servo bores, my only experience is with non hollow pin servos, thinking of the main bore. The explanation on that rebuilder site was really good (save for a couple typos.)
My '03 is probably only worth $4k or $5k. With this tranny problem, having it fixed at retail is a bit of a question mark. Thinking that while I don't love working on major problems on my daily driver myself, it makes little sense to sink big dollars into a low value car for a problem that isn't brain surgery.
Maybe twisted logic.
[BTW-Here's a picture of a roller bearing conversion I did in my Ford C-4 tranny in the rearmost (#9) thrust bushing location. Under power the gear train is thrust rearward overtaxing the bushing and tearing off the tangs. By machining an adapter ring and cutting a clearance channel in the back of the sprag hub, you can place this bearing where the doomed bushing went. Machine work by me, knowledge found on the web.]

C4No9Brg.jpg
 
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Nicely done! Very neat trick on that tranny. I did a home rebuild of a TH350 several years back which just convinced me not to do it again. Similarly, I just helped a fried do a full front end rebuild on his town car (he didn't have the cash for a shop), and that convinced me to never replace bushings and ball joints myself again.

You know how it is, sometimes you have to double check folk's knowledge base. See the questions about serpentine belts vs timing chains....

That conundrum is faced by everyone here. The resale value on these cars is just horrible. For me, I enjoy the car too much. I consider it the best drive for the price.

BTW, what's the status of the 'stang?
 
Project Logjam

Still no automatic on that thing? Still works using the SST?

Yup. Well, just missing 2nd and 5th. If you start in SST 2nd, get rolling and kick it into D4 it will be fine until it downshifts all the way to 1st. It gets caught trying to make the 1-2 so SST with no OD 5th is the dealio until I want to stack another project on the pile.

BTW, what's the status of the 'stang?

Well, the SCJ is in daily driver condition so all good there. I also have e '65 fastback I built a 422ci stroker Windsor for (AFR heads, KB pistons, comp cams etc.) that hasn't been fired. That's the car the C4 is going behind. Engine stand queen. It's on hold until kid sports (9 and 12 yrs) are done. I went to 3 soccer games over the weekend. (shrug)

422StrokerWindsor.jpg
 
Could be worth a shot, but considering the LS starts out in second gear, the wear on that particular servo bore is more than likely less than in some other applications of the 5R55N/W/S.
 
have them bored out properly and the sleeves put in with new OEM servos. Or you will just end up doing it anyways.
 
Only the original programming in the Gen I V8 cars had them starting out in 2nd gear. The Gen II V8 cars start out in 1st.
 
Hey guys, have you checked this out? It seems like a perfect fix to your problem. I am about to order it when I get a few extra bucks. http://www.fordservoboretransmissionfixsolution.com/

I ordered that solution, thought it well worth a try. Dropped my H pipe, driveline and steering rack and tilted the tranny down to see if I could access the servos. Sure enough I was able to do the fix with the engine and tranny in the car. When I pulled the suspect OD servo found this
IMG_3007_zps99e21712.jpg


Shocked that it wasn't a worn bore, but a broken servo. Put the fix servos (both of them) in and did a fluid and filter change and the tranny has been good as new. So great. Highly recommend this.
 
I ordered that solution, thought it well worth a try. Dropped my H pipe, driveline and steering rack and tilted the tranny down to see if I could access the servos. Sure enough I was able to do the fix with the engine and tranny in the car. When I pulled the suspect OD servo found this
View attachment 828561466

Shocked that it wasn't a worn bore, but a broken servo. Put the fix servos (both of them) in and did a fluid and filter change and the tranny has been good as new. So great. Highly recommend this.
i know this is 14 years later but im wondering what exactly to do to get to the servo bores. how do you tilt the transmission?
 
There is a TSB about repair of the servo bores. My 2005 LS was done back in 2011 when it had 43,600 miles on it under the extended warranty I purchased. TSB 09-12-12, I tried to attach the file but looks like it is too large. You can search the TSB on the internet.
 
There is a TSB about repair of the servo bores. My 2005 LS was done back in 2011 when it had 43,600 miles on it under the extended warranty I purchased. TSB 09-12-12, I tried to attach the file but looks like it is too large. You can search the TSB on the internet.
yes i found the TSB, that shows it with the transmission out of the car. i don’t want to take the transmission out
 

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