I have some Mobil Delvac 75W90 Im going to put in the CTS differential. Its a 2010 with the 3.0L. Ive looked around online and found that its actually pretty easy! But, does anypony know the proper fill level?
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Fill level for Cadillac CTS differential
- Thread starter Colt45ws
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Originally Posted By: Colt45ws
I have some Mobil Delvac 75W90 Im going to put in the CTS differential. Its a 2010 with the 3.0L. Ive looked around online and found that its actually pretty easy! But, does anypony know the proper fill level?
Be careful, they call for full synthetic oil in a spec that is hard to find outside of the GM Grape juice or newer lube. Also check for the need for the GM friction modifier. This isn't your fathers differential.
I have some Mobil Delvac 75W90 Im going to put in the CTS differential. Its a 2010 with the 3.0L. Ive looked around online and found that its actually pretty easy! But, does anypony know the proper fill level?
Be careful, they call for full synthetic oil in a spec that is hard to find outside of the GM Grape juice or newer lube. Also check for the need for the GM friction modifier. This isn't your fathers differential.
JHZR2
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Originally Posted By: johnachak
Be careful, they call for full synthetic oil in a spec that is hard to find outside of the GM Grape juice or newer lube.
I dont know that delvac is syn, but syn diff lube isnt that hard to find. Is there a specific spec necessary that the usual ones wont meet?
Be careful, they call for full synthetic oil in a spec that is hard to find outside of the GM Grape juice or newer lube.
I dont know that delvac is syn, but syn diff lube isnt that hard to find. Is there a specific spec necessary that the usual ones wont meet?
Im not worried about some spec. Delvac is good stuff with many approvals. I did note the possible LSD and it is something I will have to check for before I drain it. Easy enough once I get it jacked up.
1. Delvac is Full Syn. Forgot about that part.
2. It is not equipped with a LSD, as I suspected.
3. Level was about .25" below the fill hole when I started. I duplicated that. There are no leaks and that seems to be a reasonable level.
4. I am THE LUCKIEST [censored] ON THE PLANET! NO JOKE!
So that story goes like this. I was debating posting it, because it is embarrasing but I decided to anyway.
I get it jacked up and look at it. Looks super easy. I pull the fill plug and then the drain. It empties in no time. I let it continue until its just dripping.
Wipe the magnetic drain plug off while that is going on. Sort through the results for chunks. Dont find any, just iron paste.
Plug it up and start pumping fluid in. I was using the Amsoil pump which had a tip on the end of the hose, a male-to-male adapter. I'm sure you can see where I'm going with this story now.
So I get it up close to full, and I put the hose back in for another couple pumps. Pull it back out to check, and the tip is GONE!
I had a heart attack! Im going, "NO! YOU CAN'T OPEN THIS THING UP! YOU [censored]!" Im looking at how the diff is situated in the thing and the money meter is running at full tilt. Like someone put a drill on an odometer. The rear IRS has to come apart so you can get the CV shafts out. The exhaust has to come off. Then you can actually drop the driveshaft and then the unit itself.
After I calm down and study the thing some more, Im thinking the space around the carrier is about minimal. I got 1.5qts out of this thing, so its tight in there. I can even see where the reinforcement ribs get thinner so that case can bulge out around the ring gear. There isnt much room in there for it to hide.
I decided to see if I couldnt get it out through the drain. I found a clean container and drained the fresh fluid back out of it.
Once it was suitably empty I stuck a finger in there and found it quickly. It was somehow already stuck between the case and the ring gear. I went key on and put it in neutral.
It took me about 1.5-2 hours of fingering the differential through the drain hole while I was using a tire to move the ring gear back and forth. It was touch and go a couple times when I managed to lose it; but its so tight inside there. Just spinning the carrier would bring it back within reach. I ended up using a piece of wire cut from a hanger to actually get it out. It came out chewed, but intact.
Im a happy camper.
2. It is not equipped with a LSD, as I suspected.
3. Level was about .25" below the fill hole when I started. I duplicated that. There are no leaks and that seems to be a reasonable level.
4. I am THE LUCKIEST [censored] ON THE PLANET! NO JOKE!
So that story goes like this. I was debating posting it, because it is embarrasing but I decided to anyway.
I get it jacked up and look at it. Looks super easy. I pull the fill plug and then the drain. It empties in no time. I let it continue until its just dripping.
Wipe the magnetic drain plug off while that is going on. Sort through the results for chunks. Dont find any, just iron paste.
Plug it up and start pumping fluid in. I was using the Amsoil pump which had a tip on the end of the hose, a male-to-male adapter. I'm sure you can see where I'm going with this story now.
So I get it up close to full, and I put the hose back in for another couple pumps. Pull it back out to check, and the tip is GONE!
I had a heart attack! Im going, "NO! YOU CAN'T OPEN THIS THING UP! YOU [censored]!" Im looking at how the diff is situated in the thing and the money meter is running at full tilt. Like someone put a drill on an odometer. The rear IRS has to come apart so you can get the CV shafts out. The exhaust has to come off. Then you can actually drop the driveshaft and then the unit itself.
After I calm down and study the thing some more, Im thinking the space around the carrier is about minimal. I got 1.5qts out of this thing, so its tight in there. I can even see where the reinforcement ribs get thinner so that case can bulge out around the ring gear. There isnt much room in there for it to hide.
I decided to see if I couldnt get it out through the drain. I found a clean container and drained the fresh fluid back out of it.
Once it was suitably empty I stuck a finger in there and found it quickly. It was somehow already stuck between the case and the ring gear. I went key on and put it in neutral.
It took me about 1.5-2 hours of fingering the differential through the drain hole while I was using a tire to move the ring gear back and forth. It was touch and go a couple times when I managed to lose it; but its so tight inside there. Just spinning the carrier would bring it back within reach. I ended up using a piece of wire cut from a hanger to actually get it out. It came out chewed, but intact.
Im a happy camper.
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Originally Posted By: JHZR2
Originally Posted By: johnachak
Be careful, they call for full synthetic oil in a spec that is hard to find outside of the GM Grape juice or newer lube.
I dont know that delvac is syn, but syn diff lube isnt that hard to find. Is there a specific spec necessary that the usual ones wont meet?
Absolutely, at least for my CTS 4. Read the fluid specifications section in your manual. Mobil 1 is good stuff too but my mechanic had me get the original GM stuff. I was able to find 3 qts for $55. (3 because we did the front too) The dealer gets $39 a qt. the additive was only $11.
My back is bad so I can't do it myself and my mechanic is excellent and a friend. I certainly don't want to jeopardize a 100,000 mile power train warranty.
Originally Posted By: johnachak
Be careful, they call for full synthetic oil in a spec that is hard to find outside of the GM Grape juice or newer lube.
I dont know that delvac is syn, but syn diff lube isnt that hard to find. Is there a specific spec necessary that the usual ones wont meet?
Absolutely, at least for my CTS 4. Read the fluid specifications section in your manual. Mobil 1 is good stuff too but my mechanic had me get the original GM stuff. I was able to find 3 qts for $55. (3 because we did the front too) The dealer gets $39 a qt. the additive was only $11.
My back is bad so I can't do it myself and my mechanic is excellent and a friend. I certainly don't want to jeopardize a 100,000 mile power train warranty.
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You don't have a LS diff ? I thought it was standard? Hmmmm, maybe only with the DI 3.6 and awd? I'm glad all went well for you. How many miles do you have on your CTS?
Its not "mine" but I do take care of it. It has 39k on it.
Nope. Once I jacked it, I spun one wheel. They spun opposite directions.
Nope. Once I jacked it, I spun one wheel. They spun opposite directions.
Originally Posted By: Colt45ws
Its not "mine" but I do take care of it. It has 39k on it.
Nope. Once I jacked it, I spun one wheel. They spun opposite directions.
That right there saved you a lot of bucks. Good looking out actually.
Its not "mine" but I do take care of it. It has 39k on it.
Nope. Once I jacked it, I spun one wheel. They spun opposite directions.
That right there saved you a lot of bucks. Good looking out actually.
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