[Pasharin]

Hi, Guys!
As it turned out, my experience will be useful in the USA. I repaired my rear axle on my cadillac ATS 2013 AWD Performance. If you have 2.0T ATS, then you have 195mm rear axle, and not LSD. Maybe my experience will be useful for LSD, but 100% will be useful for those who have ATS 2.0T, CTS 2.0T.

It is my differential on picture.

After removing the axle you remove the cover, the differential mount, the wheels drive, we get a couple, knock out the side bearings. The heaviest are the rings on the side bearings side.

When we opened my differential, we saw that the large front bearing was broken. The bearings used in my differential were KOYO and F A G. The good news was there were numbers on the bearings. I found the bearings I needed on Alibaba (Shandong Hanke Bearing Co., Ltd. - Deep groove ball bearing,ball bearing)
Bearing numbers:
KOYO F-577158 - front large. KOYO F-574658 - front small. KOYO LM501349 / 14 - side. Seller Sarah Wang of Shandong Hanke Bearing Co., Ltd.
Numbers of gaskets and seals:
22772331 - cover gasket, 22993016 - rear axle shaft oil seal (2pcs), 92230584 - shank oil seal.
She helped with the choice, delivery and sent me all the photos with my bearings.

I found the repair manual for the 2015+ CTS 3 and explored all the information on repairing the rear differential. I made a manual for a mechanic. Rear Differential.pdf

The main thing is the tightening torque of the shaft nut, and of the rest of the fastening nuts. If you choose the wrong tightening torque, the couple may break.

The manual says: Tighten the NEW rear wheel drive shaft flange nut to 105 N.m (77 lb ft) until the pinion end play is just taken up.

Used differential in Russia - from 1500 $
New differential in Russia - from 3000 $
Used differential from Ukraine or other countries (without delivery) - from 350 $

I paid for 1 sets bearings (2 front, 2 side), all seals, the delivery, repair work - about 300 $.
I don’t know will the repair be profitable in the USA, but in Russia it was profitable.

If you have any questions, ask me. Who needs help, write. If someone wants to buy bearings, I will write the seller's phone number (Sarah Wang)

 

[angel71rs]

Excellent, appreciate the effort & info, especially the bearing part numbers. When I did a lot of diffs, I preferred US and Japan made bearings, please post updates as to your long term experience with the China sourced bearings.

Question: the procedure on diffs I worked on called for a new crush sleeve on the pinion. You would tighten the pinion nut until you achieved the required preload on the pinion bearings (you refer to them as front bearings) as measured by an inch-pound dial torque wrench.

Since the manual specifies tightening the pinion nut to 77 lb ft, have they switched to using a solid spacer in between the pinion bearings instead of a crush sleeve? Or is there nothing at all between the pinion bearings?

edit: I zoomed in on the pic with the parts in the pan and can clearly see a crush sleeve on the pinion shaft. Maybe the procedure in the manual calling for 77 lb ft is a quick cheat repair reusing the old crush sleeve vs the much more time consuming procedure using a new crush sleeve?

What are those ball bearings on the pinion shaft? Are those the pinion (front) bearings?

 

[rmfats]

It's a sad day when someone on the other side of the planet has to advise us on how to repair an American car. Why isn't GM or the company that made the differential doing this? It's just not the American way anymore.

 

[rand49er]

It's a sad day when someone on the other side of the planet has to advise us on how to repair an American car. Why isn't GM or the company that made the differential doing this? It's just not the American way anymore.

While on the CTS-V (Gen 1) forum for years, I noticed it was always one of the forum members who would blaze the way on fixes and mods (sometimes an aftermarket supplier) and do a writeup. It is, however, somewhat surprising that a writeup hasn't been done here before now especially on a component with a bit of a reputation for problems.

 

[Pasharin]

Excellent, appreciate the effort & info, especially the bearing part numbers. When I did a lot of diffs, I preferred US and Japan made bearings, please post updates as to your long term experience with the China sourced bearings.

Question: the procedure on diffs I worked on called for a new crush sleeve on the pinion. You would tighten the pinion nut until you achieved the required preload on the pinion bearings (you refer to them as front bearings) as measured by an inch-pound dial torque wrench.

Since the manual specifies tightening the pinion nut to 77 lb ft, have they switched to using a solid spacer in between the pinion bearings instead of a crush sleeve? Or is there nothing at all between the pinion bearings?

edit: I zoomed in on the pic with the parts in the pan and can clearly see a crush sleeve on the pinion shaft. Maybe the procedure in the manual calling for 77 lb ft is a quick cheat repair reusing the old crush sleeve vs the much more time consuming procedure using a new crush sleeve?

What are those ball bearings on the pinion shaft? Are those the pinion (front) bearings?

We replaced the washer (green circle), because it was crushed. The front large bearing has been broken (red circle). There was a ball bearing in the differential then, but now I have replaced it with a roller bearing. There were no other broken parts. Now the car is going fine.

It's a sad day when someone on the other side of the planet has to advise us on how to repair an American car. Why isn't GM or the company that made the differential doing this? It's just not the American way anymore.

GM repairing differentials. This is money. Why tell this to anyone?
But in Russia, our service companies ask a lot of money to repair your car. If you have a Cadillac, then you have a lot of money! But I'm not willing to pay a lot of money for something that I can fix myself. )))))

While on the CTS-V (Gen 1) forum for years, I noticed it was always one of the forum members who would blaze the way on fixes and mods (sometimes an aftermarket supplier) and do a writeup. It is, however, somewhat surprising that a writeup hasn't been done here before now especially on a component with a bit of a reputation for problems.

Maybe because you can buy new or used part. In the us the differential is not very expensive.
Now I am replacing the pistons with forged ones.

 

[angel71rs]

We replaced the washer (green circle), because it was crushed. The front large bearing has been broken (red circle). There was a ball bearing in the differential then, but now I have replaced it with a roller bearing. There were no other broken parts. Now the car is going fine.
View attachment 601662

The part in yellow looks like the crush sleeve to me. The ring bulge around it's circumference is what expands as you preload the bearings when torquing the nut. Like I said, maybe procedure in manual is a quick cheat repair.

It is disturbing that a ball bearing was originally installed at the highly stressed location by the pinion gear head. If this is normal from the factory, goes a long way to explain the high failure rate of these diffs. Ball bearings just don't have the load capacity of a roller.

What is the difference between a roller bearing and a ball bearing? | Nippon Bearing

A roller bearing is a cylindrical unit that is used to provide low-friction movement for a bushing or bearing block. A ball bearing is a spherical unit that accomplishes the same objective as a roller …

www.nbcorporation.com

Installing a roller in place of the original ball bearing is a great way to improve the reliability of the diff, so the part number you supplied for it becomes doubly important for anyone that rebuilds their diff!

I'm not surprised that the only 3 members I've seen messing with a diff rebuild are foreigners. This is a Cadillac forum, not a Camaro or Mustang forum where you would expect a much more hands on membership doing a lot of mechanical work on their cars. Add to that the much easier availability/lower cost of a diff here in the US and it's not surprising most ATS owners with a failed diff just have the assembly replaced with a new or used unit. Guys overseas faced with a $$$ quote to replace the diff are much more likely to try a rebuild.

That might change over time as the price of used ATSs drop to the point where younger more hands on guys with more enthusiasm than $ start to buy them. Might not as the Camaro might be more attractive to that crowd.

Thanks again Pasharin, outstanding work!

 

[ZeGerman]

...and you have to mention, that most differentials fail within the 5 year powertrain warranty. So no need of changing single parts. I think it will be interesting when these new diffs may start to fail as well ... after the warranty expired.

In Germany or Europe for example there is just a 3 year manufacturer warranty if you don't buy an extended guarantee.

 

[DavidATS]

...and you have to mention, that most differentials fail within the 5 year powertrain warranty. So no need of changing single parts. I think it will be interesting when these new diffs may start to fail as well ... after the warranty expired.

In Germany or Europe for example there is just a 3 year manufacturer warranty if you don't buy an extended guarantee.

I agree with what you are saying, for most in the U.S. there hasn't been a lot of years to deal with the diff problem.
Powertrain is actually better and both my diff leaks were covered under warranty, if I hadn't caught it in some ways I might have been better off if it had failed and they had to replace it.

Powertrain Warranty -
Cadillac will warrant each 2013 and newer vehicle for 6-years or 70,000-miles†, with no deductible from the original in-service date of the vehicle, for warrantable repairs which are required as a result of defects due to material and/or workmanship to the engine, transmission, or drive systems.

 

[robertorolfo]

It's a sad day when someone on the other side of the planet has to advise us on how to repair an American car. Why isn't GM or the company that made the differential doing this? It's just not the American way anymore.

Necessity is the mother of...

 

[rmfats]

The part in yellow looks like the crush sleeve to me. The ring bulge around it's circumference is what expands as you preload the bearings when torquing the nut. Like I said, maybe procedure in manual is a quick cheat repair.

View attachment 601663

It is disturbing that a ball bearing was originally installed at the highly stressed location by the pinion gear head. If this is normal from the factory, goes a long way to explain the high failure rate of these diffs. Ball bearings just don't have the load capacity of a roller.

What is the difference between a roller bearing and a ball bearing? | Nippon Bearing

A roller bearing is a cylindrical unit that is used to provide low-friction movement for a bushing or bearing block. A ball bearing is a spherical unit that accomplishes the same objective as a roller …

www.nbcorporation.com

Installing a roller in place of the original ball bearing is a great way to improve the reliability of the diff, so the part number you supplied for it becomes doubly important for anyone that rebuilds their diff!

I'm not surprised that the only 3 members I've seen messing with a diff rebuild are foreigners. This is a Cadillac forum, not a Camaro or Mustang forum where you would expect a much more hands on membership doing a lot of mechanical work on their cars. Add to that the much easier availability/lower cost of a diff here in the US and it's not surprising most ATS owners with a failed diff just have the assembly replaced with a new or used unit. Guys overseas faced with a $$$ quote to replace the diff are much more likely to try a rebuild.

That might change over time as the price of used ATSs drop to the point where younger more hands on guys with more enthusiasm than $ start to buy them. Might not as the Camaro might be more attractive to that crowd.

Thanks again Pasharin, outstanding work!

I am not an engineer, but wouldn't a ball bearing work OK if the material was hard enough? The pressure on the contact point would be significantly higher, therefore the metal should be able to handle this. I read somewhere that the bearing material was too soft. If the differential never ran low on oil would this really matter?

 

[angel71rs]

The problem is the extremely high pressure on a smaller contact point of the ball vs lower pressure being spread out on the larger contact area of a roller bearing. Much less forgiving.

In order for a ball bearing to live in this application, everything has to be just right. Lube condition, metal heat treat, metal surface finish. Anything slightly off and the metal starts to gall. Once that happens, failure is inevitable.

The spindly 7 5/8 diff used in LS1 F bodies has a rep for physically breaking, especially in M6 cars or with mods/high traction tires. But the roller bearings had a normal low failure rate.

Using a ball bearing anywhere in the diff was a big mistake IMO.

 

[rmfats]

The problem is the extremely high pressure on a smaller contact point of the ball vs lower pressure being spread out on the larger contact area of a roller bearing. Much less forgiving.

In order for a ball bearing to live in this application, everything has to be just right. Lube condition, metal heat treat, metal surface finish. Anything slightly off and the metal starts to gall. Once that happens, failure is inevitable.

The spindly 7 5/8 diff used in LS1 F bodies has a rep for physically breaking, especially in M6 cars or with mods/high traction tires. But the roller bearings had a normal low failure rate.

Using a ball bearing anywhere in the diff was a big mistake IMO.

You make complete sense. I guess it will always be a mystery as to why a company that specializes in differential design could make such a mistake. The least they could do is come out with an aftermarket rebuild kit with upgraded bearings.

 

[BKbroiler61]

Nice work. Thanks for posting.

 

[dthela]

Hi, Guys!
As it turned out, my experience will be useful in the USA. I repaired my rear axle on my cadillac ATS 2013 AWD Performance. If you have 2.0T ATS, then you have 195mm rear axle, and not LSD. Maybe my experience will be useful for LSD, but 100% will be useful for those who have ATS 2.0T, CTS 2.0T.

It is my differential on picture.
View attachment 601554 View attachment 601555

View attachment 601556 View attachment 601585


After removing the axle you remove the cover, the differential mount, the wheels drive, we get a couple, knock out the side bearings. The heaviest are the rings on the side bearings side.

View attachment 601558 View attachment 601559 View attachment 601557

When we opened my differential, we saw that the large front bearing was broken. The bearings used in my differential were KOYO and F A G. The good news was there were numbers on the bearings. I found the bearings I needed on Alibaba (Shandong Hanke Bearing Co., Ltd. - Deep groove ball bearing,ball bearing)
Bearing numbers:
KOYO F-577158 - front large. KOYO F-574658 - front small. KOYO LM501349 / 14 - side. Seller Sarah Wang of Shandong Hanke Bearing Co., Ltd.
Numbers of gaskets and seals:
22772331 - cover gasket, 22993016 - rear axle shaft oil seal (2pcs), 92230584 - shank oil seal.
She helped with the choice, delivery and sent me all the photos with my bearings.

I found the repair manual for the 2015+ CTS 3 and explored all the information on repairing the rear differential. I made a manual for a mechanic. Rear Differential.pdf

The main thing is the tightening torque of the shaft nut, and of the rest of the fastening nuts. If you choose the wrong tightening torque, the couple may break.
View attachment 601583 View attachment 601582

The manual says: Tighten the NEW rear wheel drive shaft flange nut to 105 N.m (77 lb ft) until the pinion end play is just taken up.

Used differential in Russia - from 1500 $
New differential in Russia - from 3000 $
Used differential from Ukraine or other countries (without delivery) - from 350 $

I paid for 1 sets bearings (2 front, 2 side), all seals, the delivery, repair work - about 300 $.
I don’t know will the repair be profitable in the USA, but in Russia it was profitable.

If you have any questions, ask me. Who needs help, write. If someone wants to buy bearings, I will write the seller's phone number (Sarah Wang)

LoV to know the bearing part numbers!

Maybe because you can buy new or used part. In the us the differential is not very expensive.
Now I am replacing the pistons with forged ones.

That particular diff is $1600. But you can't even get them caddy has none!

The part in yellow looks like the crush sleeve to me. The ring bulge around it's circumference is what expands as you preload the bearings when torquing the nut. Like I said, maybe procedure in manual is a quick cheat repair.

View attachment 601663

It is disturbing that a ball bearing was originally installed at the highly stressed location by the pinion gear head. If this is normal from the factory, goes a long way to explain the high failure rate of these diffs. Ball bearings just don't have the load capacity of a roller.

What is the difference between a roller bearing and a ball bearing? | Nippon Bearing

A roller bearing is a cylindrical unit that is used to provide low-friction movement for a bushing or bearing block. A ball bearing is a spherical unit that accomplishes the same objective as a roller …

www.nbcorporation.com

Installing a roller in place of the original ball bearing is a great way to improve the reliability of the diff, so the part number you supplied for it becomes doubly important for anyone that rebuilds their diff!

I'm not surprised that the only 3 members I've seen messing with a diff rebuild are foreigners. This is a Cadillac forum, not a Camaro or Mustang forum where you would expect a much more hands on membership doing a lot of mechanical work on their cars. Add to that the much easier availability/lower cost of a diff here in the US and it's not surprising most ATS owners with a failed diff just have the assembly replaced with a new or used unit. Guys overseas faced with a $$$ quote to replace the diff are much more likely to try a rebuild.

That might change over time as the price of used ATSs drop to the point where younger more hands on guys with more enthusiasm than $ start to buy them. Might not as the Camaro might be more attractive to that crowd.

Thanks again Pasharin, outstanding work!

THose particular rears with the cast iron housings go for $1600. Same problem with my CTS! THE PARTS ARENT AVAILABLE backorder indefinitely. I used the ATS rear and axles in my CTS. Perfect!

 

[ZeGerman]

I am somehow glad, that I insisted on handing out the broken diff (LSD) after it was swapped under warranty in 2019. It is stored in my basement just waiting for the new one start howling or grinding... and for me ordering new bearings. 🛠

 

[ScroggDoggy]

Has anyone else tried this repair and had any success? My pinion bearings are shot as we speak and I've been contemplating tearing into it and trying to cross reference bearing sizes to replace, so I am very glad that I found this

 

[dthela]

Great thread! But.... I have the same rear and there seems to be a roll pin holding in the axle for the planetary gears. There is no way to pull the pin out as it is flush. How did you remove the planetary axle shaft with that pin??? Other rears have a bolt holding in the shaft. Please let me know how you got the shaft out!

 

[dthela]

I see in your pictures that the entire gear system comes out in one piece but I can't see any way to access the clips on the ends of the axle shafts. One of my axle shafts is almost touching the planetary axle on one side. How do you get the axle clips out?

 

[dthela]

By the way I have a CTS4 it has the 3:27 ratio open rear like yours. The only difference between the ATS and CTS rears are the flanges for the axles. ATS has 6 bolts CTS has 8 bolts. I used an ATS rear and the ATS axles. They are slightly smaller but I'm not drag racing and it's working fine. I think the Camaro rear would work also but they have splines on both ends of the cv axles instead of the flanges on the differential ends.

 

[angel71rs]

Doesn't look like Pasharin touched the roll pin as the lavender paint looks undisturbed. Doesn't look like the axle ends have a large C clip like live axles do, has a smaller round clip. CV axles use something like this and they pop out after pressure is applied.

If you read the PDF Pasharin posted it looks like proper procedure is to pull out the axles with a slide hammer/puller. But there are tricks to pulling flanges off without using pullers.

A common one we used on industrial equipment was to thread longer bolts thru the flange and screw them down evenly to push the flange out. You might have to put flat pieces of steel to protect the diff housing/give the bolts a surface to push against.