Jim Henderson
Dedicated LVC Member
I have just finished a summer to winter long project of essentially replacing or rebuilding my driveline from the tranny back to the wheels. As I get time I plan to write up my thoughts and experience on each main component section, ie diff, rubber couplers, center carrier bearing, dropping the exhaust and splash pan(to get at the center carrier). Hopefully I will have a few pictures to throw in. Don't have pics for the differential since it was a long and dirty job and I didn't want to drag my camera thru the grease.
Work on a flat firm surface and use JACKSTANDS Always. Way too much fun having a car slide off a jack. TORQUE to SPEC. Use thread lock compound as needed and as noted in the manual. I think just the 6 rubber coupler bolts and maybe the 3 Diff bolts and the caliper mount bolts are noted. Read the manual before you begin, RTFM.
I am making these posts since the online shop manual we use is OK but far from descriptive about "How to do" xyz.
This is probably the longest of my pending posts because 1) It was the most involved task and 2) I am known to be a bit long winded.
Anyway... My transmission started showing signs of impending failure this last summer, with about 170,000 miles on it. Actually the dealer did a minor rebuild at about 20-30K miles due to noise. They also replaced the pinion seal per TSB around 30-40K miles. Typical LS issues. My Differential started a barely noticable whine at around 60K miles or so and gradually got louder over the next 110,000 miles or so. I suspect the dealer screwed up but no proof.
I believe all the driveline parts I have replaced this year are all related to the initial differential failure and age. The noise from the diff by this point was pretty noticable and I was thinking I would need to replace the CV and or wheel bearing after the tranny shop was done, which I did do but didn't need to. Stories on those later.
Anyway, when I got my car back from the tranny rebuild shop, I only got about 40 miles on the odo before my shift knob literally exploded and my car no longer had any forward acceleration. Previously I warned the shop owner that my car was making ominous screech metal noises but he said OK to drive, wrong. The metal to metal noise was the rubebr coupler bolts wobbling around in the mounting flanges of the tranny, driveshaft and diff.
Diagnosis by the tranny shop showed that the front rubber coupler from the tranny to the front half of the split drive shaft aka Torque Tube had disintegrated and wrapped around the shifter linkage thus killing my shift knob and any control over the tranny. Note the noise about 1 mile before total failure was kind of a rapid sputtering sound, I thought it was an exhaust leak. It was actually rubber slapping around making the noise, then kaboom.
They replaced both couplers as a goodwill gesture only charging me about $400 to do both couplers, ie the parts cost of about $90 each and the cost of a tow($150). BTW Rubber couplers from Rockauto were less than $50 each. Maybe out of stock now?
A few weeks later, I noticed there was much more driveline noise. I crawled around under the car and noticed that the brand new rear coupler showed distinct cracks in the rubber and had grey threads hanging out. I took it back to the shop and they replaced it, no charge. They did a closer inspection and said that the pinion or input shaft of my differential wobbled about 1/8 inch around the centerline. They believed this was causing excess wobble at the rubber coupler leading to it's failure. I believe this is possible and in fact is why earlier I said the various parts of the driveline that failed were related to the diff wobble. Also, unknown at the time was that the center carrier bearing rubber mount was failing and contributing to wobble. Wish the tranny shop had inspected that. It can be seen from the front of the car looking back into the driveshaft tunnel.
I have pics of the couplers which I will post in that separate posting.
Anyway... Replacing the Differential is not that difficult. This is one part of the LS that I actually feel IS easy to service. The main difficulty is that the diff is heavy and you will surely need a transmission jack.
To remove the differential(Replacement is the reverse except as I will note), you need to remove the axles, the rear drive shaft coupler and that's it. Harder than written but easier than I thought and not as hard as a live or straight axle/diff.
ANYONE who has done a rear brake job and removed the rotor can do a differential.
To remove the CV/axles you can do it either the way the manual says, ie remove the brakes, rotor, wheel assembly then slide the cv out, or do it the way I did when I did not have access to a long breaker bar or impact wrench to undo the big axle nut, 1 1/4 inch socket.
To remove it my way which saves the step of having to remove the wheel assembly and undoing that big axle nut, just do the following steps below. The disadvantage is that the wheel assembly/CV joint/axle is clumsier to handle and heavier than if you remove the wheel assembly first. Actually the Wheel assembly can be swung upwards to allow removal of the CV Axle per the manual, but it is a beach.
1) Remove tire
2) Remove brake caliper. Also remove the speed sensor, it is the only thing with a wire to it and sits on top and is maybe as big as a cigarette butt.
3) Remove the frame the brake caliper sits in. It is Kind of horseshoe shapped and held in place by 2 bolts. These are tight and will take a bit of grunt to break loose(thread locked). Actually I am not sure you need to do this unless you need to remove the rotor.
4) Remove the 3 bolts/nuts and the one nut from the ball joints and sway bar etc. There is one large bolt/nut horizontally under the wheel assm. One large bolt/nut vertically and one small bolt/nut thru a ball joint and one nut only on the upper ball joint(this is the one you leave in place doing it per the manual). The big nut on the underside of the top ball joint is the hardest to do since it is in a tight spot, ie no room for a socket and you have to hold the center stud from turning by using a small open end wrench. I used a tiny adjustable wrench. You will need a larger open end wrench to turn the big nut. Once loose it is easy. I forget what size wrenches I used but one was a 18mm open end.
5)Once the wheel assembly is untied, 4 places you need to remove the CV/Axle. If you are lucky, you can just slide it out.
5A) More likely you will need to use some pry bar(big flat screwdriver) between the Differential and the inner CV joint. You will not need a lot of force, just a nudge. It will just sort of pop out.
5B) I helps if you have a buddy to hold one end of the CV and you do the other to slide it out without hitting the CV splines on anything or tearing up the rubber seal on the differential axle hole.
6) MARK the mounting flanges of the diff and drive shaft, ie index or clock those muthers. Actually this is only needed IF you reuse your old diff or are replacing other parts not the diff. The drive shaft etc are balanced at the factory to minimize vibration. Remove the rubber coupler or at least remove the bolt/nut/washer, 6 places. These are maybe tight depending on whether vibration loosened them. You will need a 17mm for the bolt head and an 18mm for the nut. An air wrench comes in very handy here if you have the space. Those bolts stick out a good 1/2 inch or more so you will be turning a long time and there is only enough space to get in maybe 60degrees at a pop. You probably only have room for an air wrench at the front of the coupler since the diff input flange and differential gets in the way for the other side.
6A) The bolt head/nuts alternate front to back every other hole.
7) Once all the couplers and axles are out it is time it is time to drop the diff. At the junk yard I literally did drop it, right into a handy tire just sitting around the yard. There are only 3 bolts and ONE nut holding it all in place. Notice I said one nut. I spent an hour trying to figure out why I couldn't remove the vertical bolt since I assumed it was threaded into the diff. Wrong, there is a small metal bracket attached to a frame rail above the diff, and the nut sits in there.
7A) Remove the vertical bolt and nut. Note, the bolt head I THINK is 15mm while the nut is something like 18 maybe 19mm. The difference threw me since I don't recall too many cars I worked on with different bolt/nut sizes. There is almost no room to get at the top nut. It sits inside the metal braket and there wasn't any room for a socket and not even a open end wrench. I had to use an box end wrench which just barely fit into the bracket. If I recall the only access is from the front of the car parallel to the drive shaft. BTW be sure the drive shaft is held in place with wire or something. You don't want a drive shaft shaped knot in your head when every thing lets go.
7B) The last 2 bolts are all that is left. You almost certainly must use a tranny jack to do this, especially when putting the new diff in. You will need an offset box end wrench, 18mm for the two bolts. The bolts are between the trunk well and the frame rail holding the rubber donuts which hold the diff. An 18mm socket and 3/8 drive might fit. My several different 1/2 inch drive ratchets and breaker would not fit. I could not get an air wrench with universal in either. The 3/8 will need a breaker cheater handle. It is 50/50 whether you can break them lose with just the offset box ends. I had to use a cheater on 1 bolt of my car, but no problem with the donor diff. MAKE SURE The tranny jack is in place or something to catch the diff, besides your head. The diff drops suddenly when the last threads of the bolts are free. Keep an eye on that drive shaft, remember. BTW these bolts are long and will turn for quite awhile. I think mine stuck out 1/4 inch from the donuts before they were at the end of the threads.
That is it! other than putting the replacement in place and buttoning things up. It took me maybe 2 hours moving slowly at the junk yard removing the donor.
To Install the differential is pretty much the reverse with the note that the hardest part is lining up the 2 horizontal bolts with the mating holes in the differential. A tranny jack or something is mandatory at this point unless you are built like a Young Hulk Hogan or can bench press 100+pounds with only a few inches to work in.
8) Get the diff in place and loosely insert the 3 mounting bolts. I like the vertical first to kind of keep things from dropping, then the two horizontals. While there is room, things are loose remember, put the NEW rubber coupling in place and loosely put in the 6 bolt/nut/washer sets. Remember to set the mounting flanges in their proper indexed or clocked postion(if required) from the reference marks you DID put in before dropping it right? Jockeying the differential to get the two horizontal bolts was the hardest part for me, even with a tranny jack, but then my jack didn't have the proper mounts to hold my diff from sliding around as I maneuvered the jack on my driveway which is on a slight slope, bword.
9)Once things are lined up tighten down the 2 horizontal and 1 vertical differential bolts
10) Tighten up the 6 rubber coupler bolts, 60 foot pounds I believe. Note that the rubber coupler has 6 steel inserts alternating with a short piece(nose?) sticking out every other one in opposite directions. The insert sticking out fits into a counter bore or hole around the flanges of the diff and drive shaft. Match them up. Washer and nut against rubber, bolt head against flange, insert extention in counter bore. Note there is a procedure in the manual where you can balance the individual bolt/nut sets to minimize vibration. I am not sure anyone does this except maybe factory mech.
11) Slide the CV Axle in and SEAT IT. A buddy is real handy here to handle the clumsy weight ot the wheel/axle/CV set. DO NOT allow the CV splines to scrape against anything and do not let it hit the rubber axle seal. It may be worth replacing the seal at this time anyway since it is cheap and doing it later is a pita. Slide the axle til it stops and then you will probably need to give it a good nudge to get it to "snap" into place inside the diff. Not hard to do it you have a buddy taking the weight off things. Do NOT FORCE, it should just snap into place.
12) Replace the speed sensor, the caliper frame and the caliper, maybe the rotor and wheel assembly if you did remove them before. And you are pretty much done.
Torque to spec, make sure you don't have any spare parts and be sure the diff fluid is topped up. Take it for a drive to see if there is any vibration or buzz. Buzzing usually means the inserts on the rubber coupler are not properly seated in the flange counter bore. Or worse, a rubber coupler is damaged or something up the line is loose, like the center carrier bearing which I will discuss in a separate post.
If you don't run into any surprises(aren't there always?) you can probably easily complete the whole remove and replace in a afternoon. maybe even 3 or 4 hours.
Good Luck,
Jim Henderson
Work on a flat firm surface and use JACKSTANDS Always. Way too much fun having a car slide off a jack. TORQUE to SPEC. Use thread lock compound as needed and as noted in the manual. I think just the 6 rubber coupler bolts and maybe the 3 Diff bolts and the caliper mount bolts are noted. Read the manual before you begin, RTFM.
I am making these posts since the online shop manual we use is OK but far from descriptive about "How to do" xyz.
This is probably the longest of my pending posts because 1) It was the most involved task and 2) I am known to be a bit long winded.
Anyway... My transmission started showing signs of impending failure this last summer, with about 170,000 miles on it. Actually the dealer did a minor rebuild at about 20-30K miles due to noise. They also replaced the pinion seal per TSB around 30-40K miles. Typical LS issues. My Differential started a barely noticable whine at around 60K miles or so and gradually got louder over the next 110,000 miles or so. I suspect the dealer screwed up but no proof.
I believe all the driveline parts I have replaced this year are all related to the initial differential failure and age. The noise from the diff by this point was pretty noticable and I was thinking I would need to replace the CV and or wheel bearing after the tranny shop was done, which I did do but didn't need to. Stories on those later.
Anyway, when I got my car back from the tranny rebuild shop, I only got about 40 miles on the odo before my shift knob literally exploded and my car no longer had any forward acceleration. Previously I warned the shop owner that my car was making ominous screech metal noises but he said OK to drive, wrong. The metal to metal noise was the rubebr coupler bolts wobbling around in the mounting flanges of the tranny, driveshaft and diff.
Diagnosis by the tranny shop showed that the front rubber coupler from the tranny to the front half of the split drive shaft aka Torque Tube had disintegrated and wrapped around the shifter linkage thus killing my shift knob and any control over the tranny. Note the noise about 1 mile before total failure was kind of a rapid sputtering sound, I thought it was an exhaust leak. It was actually rubber slapping around making the noise, then kaboom.
They replaced both couplers as a goodwill gesture only charging me about $400 to do both couplers, ie the parts cost of about $90 each and the cost of a tow($150). BTW Rubber couplers from Rockauto were less than $50 each. Maybe out of stock now?
A few weeks later, I noticed there was much more driveline noise. I crawled around under the car and noticed that the brand new rear coupler showed distinct cracks in the rubber and had grey threads hanging out. I took it back to the shop and they replaced it, no charge. They did a closer inspection and said that the pinion or input shaft of my differential wobbled about 1/8 inch around the centerline. They believed this was causing excess wobble at the rubber coupler leading to it's failure. I believe this is possible and in fact is why earlier I said the various parts of the driveline that failed were related to the diff wobble. Also, unknown at the time was that the center carrier bearing rubber mount was failing and contributing to wobble. Wish the tranny shop had inspected that. It can be seen from the front of the car looking back into the driveshaft tunnel.
I have pics of the couplers which I will post in that separate posting.
Anyway... Replacing the Differential is not that difficult. This is one part of the LS that I actually feel IS easy to service. The main difficulty is that the diff is heavy and you will surely need a transmission jack.
To remove the differential(Replacement is the reverse except as I will note), you need to remove the axles, the rear drive shaft coupler and that's it. Harder than written but easier than I thought and not as hard as a live or straight axle/diff.
ANYONE who has done a rear brake job and removed the rotor can do a differential.
To remove the CV/axles you can do it either the way the manual says, ie remove the brakes, rotor, wheel assembly then slide the cv out, or do it the way I did when I did not have access to a long breaker bar or impact wrench to undo the big axle nut, 1 1/4 inch socket.
To remove it my way which saves the step of having to remove the wheel assembly and undoing that big axle nut, just do the following steps below. The disadvantage is that the wheel assembly/CV joint/axle is clumsier to handle and heavier than if you remove the wheel assembly first. Actually the Wheel assembly can be swung upwards to allow removal of the CV Axle per the manual, but it is a beach.
1) Remove tire
2) Remove brake caliper. Also remove the speed sensor, it is the only thing with a wire to it and sits on top and is maybe as big as a cigarette butt.
3) Remove the frame the brake caliper sits in. It is Kind of horseshoe shapped and held in place by 2 bolts. These are tight and will take a bit of grunt to break loose(thread locked). Actually I am not sure you need to do this unless you need to remove the rotor.
4) Remove the 3 bolts/nuts and the one nut from the ball joints and sway bar etc. There is one large bolt/nut horizontally under the wheel assm. One large bolt/nut vertically and one small bolt/nut thru a ball joint and one nut only on the upper ball joint(this is the one you leave in place doing it per the manual). The big nut on the underside of the top ball joint is the hardest to do since it is in a tight spot, ie no room for a socket and you have to hold the center stud from turning by using a small open end wrench. I used a tiny adjustable wrench. You will need a larger open end wrench to turn the big nut. Once loose it is easy. I forget what size wrenches I used but one was a 18mm open end.
5)Once the wheel assembly is untied, 4 places you need to remove the CV/Axle. If you are lucky, you can just slide it out.
5A) More likely you will need to use some pry bar(big flat screwdriver) between the Differential and the inner CV joint. You will not need a lot of force, just a nudge. It will just sort of pop out.
5B) I helps if you have a buddy to hold one end of the CV and you do the other to slide it out without hitting the CV splines on anything or tearing up the rubber seal on the differential axle hole.
6) MARK the mounting flanges of the diff and drive shaft, ie index or clock those muthers. Actually this is only needed IF you reuse your old diff or are replacing other parts not the diff. The drive shaft etc are balanced at the factory to minimize vibration. Remove the rubber coupler or at least remove the bolt/nut/washer, 6 places. These are maybe tight depending on whether vibration loosened them. You will need a 17mm for the bolt head and an 18mm for the nut. An air wrench comes in very handy here if you have the space. Those bolts stick out a good 1/2 inch or more so you will be turning a long time and there is only enough space to get in maybe 60degrees at a pop. You probably only have room for an air wrench at the front of the coupler since the diff input flange and differential gets in the way for the other side.
6A) The bolt head/nuts alternate front to back every other hole.
7) Once all the couplers and axles are out it is time it is time to drop the diff. At the junk yard I literally did drop it, right into a handy tire just sitting around the yard. There are only 3 bolts and ONE nut holding it all in place. Notice I said one nut. I spent an hour trying to figure out why I couldn't remove the vertical bolt since I assumed it was threaded into the diff. Wrong, there is a small metal bracket attached to a frame rail above the diff, and the nut sits in there.
7A) Remove the vertical bolt and nut. Note, the bolt head I THINK is 15mm while the nut is something like 18 maybe 19mm. The difference threw me since I don't recall too many cars I worked on with different bolt/nut sizes. There is almost no room to get at the top nut. It sits inside the metal braket and there wasn't any room for a socket and not even a open end wrench. I had to use an box end wrench which just barely fit into the bracket. If I recall the only access is from the front of the car parallel to the drive shaft. BTW be sure the drive shaft is held in place with wire or something. You don't want a drive shaft shaped knot in your head when every thing lets go.
7B) The last 2 bolts are all that is left. You almost certainly must use a tranny jack to do this, especially when putting the new diff in. You will need an offset box end wrench, 18mm for the two bolts. The bolts are between the trunk well and the frame rail holding the rubber donuts which hold the diff. An 18mm socket and 3/8 drive might fit. My several different 1/2 inch drive ratchets and breaker would not fit. I could not get an air wrench with universal in either. The 3/8 will need a breaker cheater handle. It is 50/50 whether you can break them lose with just the offset box ends. I had to use a cheater on 1 bolt of my car, but no problem with the donor diff. MAKE SURE The tranny jack is in place or something to catch the diff, besides your head. The diff drops suddenly when the last threads of the bolts are free. Keep an eye on that drive shaft, remember. BTW these bolts are long and will turn for quite awhile. I think mine stuck out 1/4 inch from the donuts before they were at the end of the threads.
That is it! other than putting the replacement in place and buttoning things up. It took me maybe 2 hours moving slowly at the junk yard removing the donor.
To Install the differential is pretty much the reverse with the note that the hardest part is lining up the 2 horizontal bolts with the mating holes in the differential. A tranny jack or something is mandatory at this point unless you are built like a Young Hulk Hogan or can bench press 100+pounds with only a few inches to work in.
8) Get the diff in place and loosely insert the 3 mounting bolts. I like the vertical first to kind of keep things from dropping, then the two horizontals. While there is room, things are loose remember, put the NEW rubber coupling in place and loosely put in the 6 bolt/nut/washer sets. Remember to set the mounting flanges in their proper indexed or clocked postion(if required) from the reference marks you DID put in before dropping it right? Jockeying the differential to get the two horizontal bolts was the hardest part for me, even with a tranny jack, but then my jack didn't have the proper mounts to hold my diff from sliding around as I maneuvered the jack on my driveway which is on a slight slope, bword.
9)Once things are lined up tighten down the 2 horizontal and 1 vertical differential bolts
10) Tighten up the 6 rubber coupler bolts, 60 foot pounds I believe. Note that the rubber coupler has 6 steel inserts alternating with a short piece(nose?) sticking out every other one in opposite directions. The insert sticking out fits into a counter bore or hole around the flanges of the diff and drive shaft. Match them up. Washer and nut against rubber, bolt head against flange, insert extention in counter bore. Note there is a procedure in the manual where you can balance the individual bolt/nut sets to minimize vibration. I am not sure anyone does this except maybe factory mech.
11) Slide the CV Axle in and SEAT IT. A buddy is real handy here to handle the clumsy weight ot the wheel/axle/CV set. DO NOT allow the CV splines to scrape against anything and do not let it hit the rubber axle seal. It may be worth replacing the seal at this time anyway since it is cheap and doing it later is a pita. Slide the axle til it stops and then you will probably need to give it a good nudge to get it to "snap" into place inside the diff. Not hard to do it you have a buddy taking the weight off things. Do NOT FORCE, it should just snap into place.
12) Replace the speed sensor, the caliper frame and the caliper, maybe the rotor and wheel assembly if you did remove them before. And you are pretty much done.
Torque to spec, make sure you don't have any spare parts and be sure the diff fluid is topped up. Take it for a drive to see if there is any vibration or buzz. Buzzing usually means the inserts on the rubber coupler are not properly seated in the flange counter bore. Or worse, a rubber coupler is damaged or something up the line is loose, like the center carrier bearing which I will discuss in a separate post.
If you don't run into any surprises(aren't there always?) you can probably easily complete the whole remove and replace in a afternoon. maybe even 3 or 4 hours.
Good Luck,
Jim Henderson
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