Had to service a Cadillac SRX rear diff today...

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Looked up the fluid... There's 2 on this unit. It's a Haldex supplied clutch pack system, almost identical to what's used in Saab, Ford, and Volvo.

The fluid for the differential clutch pack, GM part #88863349, was almost $64 a quart, my price! I've seen some insanely priced fluid, but c'mon. It says right on the bottle that it's just 75w90. What could be so special about this stuff?
 
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Motorcraft full-syn 75w90 GL4 equivalent retials for half the price.
 
Originally Posted By: Marco620
GM just trying to rip people to save their Union bailout.


Yep, GM is the only manufacturer to ever overcharge for fluids!
 
I don't understand why they call for GL-4 MTF in a clutch-pack rear limited-slip rear diff.

I would think a GL-5 gear lube with limited slip additive would make a lot more sense. I'm sure I'm missing something.
 
Originally Posted By: clinebarger
Originally Posted By: Marco620
GM just trying to rip people to save their Union bailout.


Yep, GM is the only manufacturer to ever overcharge for fluids!


Yeah, try owning an Audi.
I had one of those, with it's special purple coolant and special PS fluid.

My next car was a GM.
 
Originally Posted By: gathermewool
I don't understand why they call for GL-4 MTF in a clutch-pack rear limited-slip rear diff.

I would think a GL-5 gear lube with limited slip additive would make a lot more sense. I'm sure I'm missing something.


There are two separate fluids in rear axle. One fluid lives with the hypoid gearset and lubricates it, along with all the bearings and the rest of the typical axle components. This fluid spec’d here is a regular synthetic 75W90 GL5.

The other lives within the clutch pack, which is separate from the axle lube described above. The purpose of the fluid is to line the clutch pack and control the lockup characteristics of the clutch. Since there is no hypoid gearset, a GL5 fluid and it’s extreme pressure additives aren’t required. The really important part of this fluid is the additive pack and the friction modifiers.

The 88863349 fluid is specific to the Haldex clutch. It’s not the typical GL4 manual transmission fluid. Honestly, I’ve never seen it in the black Delco bottle that was posted above. I’ve only seen it in a silver cylindrical bottle with a prominent “Made in Sweden” sticker on it and German translations on the label. Saab was a prominent user of this fluid when they rolled out the Haldex XWD system.

My advice: Use whatever you like for the axle, but the 88863349 fluid is quite specific for the Haldex. I don’t think you’ll find an appropriate alternative.
 
^^^ this ^^^. you do not want to monkey around with the fluid for the haldex components. If this is the same unit used in those europeans, it is hard on fluid. aside from a suggested aggressive service interval on this, a substitute won't only behave differently, but could also lead to early clutch failure.
 
Originally Posted By: MrHorspwer
Originally Posted By: gathermewool
I don't understand why they call for GL-4 MTF in a clutch-pack rear limited-slip rear diff.

I would think a GL-5 gear lube with limited slip additive would make a lot more sense. I'm sure I'm missing something.


There are two separate fluids in rear axle. One fluid lives with the hypoid gearset and lubricates it, along with all the bearings and the rest of the typical axle components. This fluid spec’d here is a regular synthetic 75W90 GL5.

The other lives within the clutch pack, which is separate from the axle lube described above. The purpose of the fluid is to line the clutch pack and control the lockup characteristics of the clutch. Since there is no hypoid gearset, a GL5 fluid and it’s extreme pressure additives aren’t required. The really important part of this fluid is the additive pack and the friction modifiers.

The 88863349 fluid is specific to the Haldex clutch. It’s not the typical GL4 manual transmission fluid. Honestly, I’ve never seen it in the black Delco bottle that was posted above. I’ve only seen it in a silver cylindrical bottle with a prominent “Made in Sweden” sticker on it and German translations on the label. Saab was a prominent user of this fluid when they rolled out the Haldex XWD system.

My advice: Use whatever you like for the axle, but the 88863349 fluid is quite specific for the Haldex. I don’t think you’ll find an appropriate alternative.


Had to google srx haldex to show the two seperate parts of the rear end.

 
Originally Posted By: MrHorspwer
Originally Posted By: gathermewool
I don't understand why they call for GL-4 MTF in a clutch-pack rear limited-slip rear diff.

I would think a GL-5 gear lube with limited slip additive would make a lot more sense. I'm sure I'm missing something.


There are two separate fluids in rear axle. One fluid lives with the hypoid gearset and lubricates it, along with all the bearings and the rest of the typical axle components. This fluid spec’d here is a regular synthetic 75W90 GL5.

The other lives within the clutch pack, which is separate from the axle lube described above. The purpose of the fluid is to line the clutch pack and control the lockup characteristics of the clutch. Since there is no hypoid gearset, a GL5 fluid and it’s extreme pressure additives aren’t required. The really important part of this fluid is the additive pack and the friction modifiers.

The 88863349 fluid is specific to the Haldex clutch. It’s not the typical GL4 manual transmission fluid. Honestly, I’ve never seen it in the black Delco bottle that was posted above. I’ve only seen it in a silver cylindrical bottle with a prominent “Made in Sweden” sticker on it and German translations on the label. Saab was a prominent user of this fluid when they rolled out the Haldex XWD system.

My advice: Use whatever you like for the axle, but the 88863349 fluid is quite specific for the Haldex. I don’t think you’ll find an appropriate alternative.


Exactly. Just like the rear diffs on Acuras. Use the wrong fluid and the clutch packs will be jumping/binding every time you take a corner. But most of ours have a separate clutch pack on each axle side that are operated independently, not just one for the whole diff.

The GM stuff is still a [censored] of a lot cheaper than the BMW AWD unit fluid my old E90 used. Worst part about that was the unit used 0.6L, and they sold it in 1.0L amounts. Doh!
 
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Originally Posted By: mightymousetech
But most of ours have a separate clutch pack on each axle side that are operated independently, not just one for the whole diff.


If you look at the cutaway photo above, you can see the two clutch packs. The one at the differential input (where the prop shaft would attach) is the "whole diff" clutch that controls power flow into the rear differential.

On the side of the input clutch pack is the clutch pump. There are two hydraulic lines that exit and go up and over the differential, into a clutch pack on the output side (where an axle shaft would bolt to). This clutch pack is the "eLSD" that controls power flow between the left and right rear wheels.

GM introduced this system with Haldex on Saabs (just before they were shut down, unfortunately). It also received use on the Cadillac SRX (twin to the Saab 9-4x) and numerous Epsilon platform vehicles (Opel Insignia, Buick Regal and Lacrosse, and Cadillac XTS). I believe the XTS is the last remaining vehicle still using this system. Most new GM's use an AWD system from GKN.
 
Originally Posted By: MrHorspwer
Originally Posted By: mightymousetech
But most of ours have a separate clutch pack on each axle side that are operated independently, not just one for the whole diff.


If you look at the cutaway photo above, you can see the two clutch packs. The one at the differential input (where the prop shaft would attach) is the "whole diff" clutch that controls power flow into the rear differential.

On the side of the input clutch pack is the clutch pump. There are two hydraulic lines that exit and go up and over the differential, into a clutch pack on the output side (where an axle shaft would bolt to). This clutch pack is the "eLSD" that controls power flow between the left and right rear wheels.

GM introduced this system with Haldex on Saabs (just before they were shut down, unfortunately). It also received use on the Cadillac SRX (twin to the Saab 9-4x) and numerous Epsilon platform vehicles (Opel Insignia, Buick Regal and Lacrosse, and Cadillac XTS). I believe the XTS is the last remaining vehicle still using this system. Most new GM's use an AWD system from GKN.


Thank you!
 
Does the Haldex system on the SRX require different fluid for the hypoid gearset vs the clutch packs?

On the Audi and VW MQB platform, the rear Haldex and diff have separate and specific fluids.
 
Nothing special except the bottle says "AC DELCO" which means it is more than twice the money of an aftermarket product. A complimentary fire extinguisher should be included when they burn you.
 
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Yep, this is no different than the fluid required for my ZF 8 speed in our RAM. It's 40 something bucks a quart at the stealership.

I bought custom blended for half that from BND...
 
Originally Posted By: MrHorspwer
Originally Posted By: gathermewool
I don't understand why they call for GL-4 MTF in a clutch-pack rear limited-slip rear diff.

I would think a GL-5 gear lube with limited slip additive would make a lot more sense. I'm sure I'm missing something.


There are two separate fluids in rear axle. One fluid lives with the hypoid gearset and lubricates it, along with all the bearings and the rest of the typical axle components. This fluid spec’d here is a regular synthetic 75W90 GL5.

The other lives within the clutch pack, which is separate from the axle lube described above. The purpose of the fluid is to line the clutch pack and control the lockup characteristics of the clutch. Since there is no hypoid gearset, a GL5 fluid and it’s extreme pressure additives aren’t required. The really important part of this fluid is the additive pack and the friction modifiers.

The 88863349 fluid is specific to the Haldex clutch. It’s not the typical GL4 manual transmission fluid. Honestly, I’ve never seen it in the black Delco bottle that was posted above. I’ve only seen it in a silver cylindrical bottle with a prominent “Made in Sweden” sticker on it and German translations on the label. Saab was a prominent user of this fluid when they rolled out the Haldex XWD system.

My advice: Use whatever you like for the axle, but the 88863349 fluid is quite specific for the Haldex. I don’t think you’ll find an appropriate alternative.


Thank you!
 
I remember the first time I changed the manual transmission oil in my 1999 Wrangler(back in 2003); the only approved oil was a magic Jeep elixir that sold for $15/quart. The next time I changed it the approved oil was NLA- and the Jeep approved replacement was 10W-30 motor oil.
 
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