2008 Cadillac CTS, RWD, Rear Differential Fluid Change

How to change the rear differential fluid in a 2008 Cadillac CTS, Rear Wheel Drive (RWD) vehicle.

[@bslav94pgt]

I used the GM oil and a cheap Amazon transfer pump made the job easier than squeezing the bag. I do like that setup

[@theazguy]

Update: After changing out the fluid there was still a grumbling sound when doing low speed turns. I ended up changing the fluid again using the GM 4 oz limited slip additive and some Mobile 1 synthetic gear oil. After that the grumbling sound went away. The Valvoline gear oil stated it had the friction modifier already in it but it didn't seem to work well for this application.

[@RVelez20]

What fixed it ? I have same problem sounds like coming from the rear wheel but once your rolling I don’t hear it

[@theazguy]

@iSaid209 after using that Valvoline gear oil and not using the limited-slip additive the car would still make a grumbling sound while doing turns in a parking lot. I ended up replacing the gear oil again with Mobil 1 and I added 4 Oz of the limited-slip additive and that completely removed the noise.

[@93cutlasi.s15]

Did this fix yours ?

[@93cutlasi.s15]

@rvelez

[@theazguy]

@@93cutlasi.s15 I ended up changing the fluid again using the GM 4 oz limited slip additive and some Mobile 1 synthetic gear oil. After that the grumbling sound went away. The Valvoline gear oil stated it had the friction modifier already in it but it didn't seem to work well for this application.

[@brianholmvick958]

This helped me Ty

[@theazguy]

If you are the only person this video ever helps, then it was totally worth it! :)

[@williamrivera6818]

Good job

[@hwfranjr]

Might need some tubing to squirt,lol

[@theazguy]

It was a tight fit with that bag lol. The second time I used a pump for the Mobil 1.

[@oscardiaz6804]

What kind of lift are you using? It looks awesome for a home garage.

[@theazguy]

It's called Quick Jack and it's freakin awesome! I wish I would have purchased it a lot sooner honestly.

[@ithinkihaveebola5238]

Hey I'm interested in a 2014 Cadillac ATS with 55,000 miles on it and I've seen some people said they're rear differential went bad and some people that said they never replaced/ repair their rear differential. Does changing the differential fluid prevent rear differential problems?

[@chvydrptop]

Thanks for the video! When you had the problem could you hear the grumbling all the time? I can hear it all the time, more so on highway with new tires. I just put the car up and sure enough when I turn the wheel I can hear the sound and it sounds like its coming from the rear differential. Only 97k on the car.

[@theazguy]

On mine I could mostly hear it when I was driving in a parking lot or doing tight turns, not when I was driving the car straight down the road. It didn't go away for me until I used the Mobil 1 and the GM differential additive. The gear oil with the additive already in it didn't work for me.

[@chvydrptop]

@@theazguy Thanks I am going to give this a try.

[@chvydrptop]

@@theazguy Do you know if you 08 has a limited slip rear end (should have code g80 in the trunk parts list). I just pulled the fluid on ours, fluid is golden clean. I looked up the alldata on the car and it could have a limited slip diff or non. Limited both rear tires would spin in the same direction when lifted off ground.

[@theazguy]

@@chvydrptop I'm not sure which differential it had. I've sold the car so I can't check for you, I'm sorry.

[@brhom-ll9nd]

I have the same sound, recently i change the tires and i her the sound at 60 to 80 miles and i check the differential oil its clean and full. do you solve the problem?

[@woundedplayz9362]

is this the additive you used ACDelco 10-4003 - Limited Slip Axle Lubricant Additive 4 oz ?

[@woundedplayz9362]

and do i need to buy 2 one for each bottle of mobil 1?

[@theazguy]

You are correct, I used ACDelco GM Original Equipment 10-4003 Limited Slip Axle Lubricant Additive - 4 oz and you only need to use one bottle for it to complete the job.

[@woundedplayz9362]

@@theazguy much appreciated i have a ‘12 cts 8-12 seem to be the exact same no problems with my differential but 155k and i almost guarantee its been the same fluid trying to do sum preventive maintenance

[@RyanOfstie]

29 ft lbs on the plugs. Over-tighten, and they will seize up and you won't get them out next time... gootentite won't cut it ;)

[@grahamholmes9737]

How many litres/oz does the diff need

[@theazguy]

I used the 4oz limited slip additive and then used almost 2 quarts of gear oil.

[@hwfranjr]

Theses plugs are suppose to be torqued,lol😂😂😂😂😂,DONT Need them falling out,😂😂😂😂😂