Chevy and GMC Duramax Diesel Forum

Chevy and GMC Duramax Diesel Forum (https://www.duramaxforum.com/forum/)
-   Alternative Fuels - Diesel - Additives - Lubricants (https://www.duramaxforum.com/forum/alternative-fuels-diesel-additives-lubricants/)
-   -   Noisy differential after fluid change? (https://www.duramaxforum.com/forum/alternative-fuels-diesel-additives-lubricants/994167-noisy-differential-after-fluid-change.html)

GMCdiesel 04-12-2019 10:31 AM

Noisy differential after fluid change?
 
I replaced my differential fluid with Valvoline full synthetic oil and now my differential is noisy. It drives me nuts.
Should I just put AC Delco gear oil back in?
What oil are you using?

2015.5 GMC 3500 dually.

J83 04-12-2019 10:45 AM

Quote:

Originally Posted by GMCdiesel (Post 12145935)
I replaced my differential fluid with Valvoline full synthetic oil and now my differential is noisy. It drives me nuts.
Should I just put AC Delco gear oil back in?
What oil are you using?

2015.5 GMC 3500 dually.

ive run mobile 1, valvoline and lucas at different points and saw no change in noise from the rear end. Did you maybe use the wrong viscosity? did you add any slip modifiers or does the fluid you purchased contain any?

GMCdiesel 04-12-2019 11:43 AM

I used 75w90. It's for limited slip differential.

J83 04-12-2019 01:14 PM

Quote:

Originally Posted by GMCdiesel (Post 12145955)
I used 75w90. It's for limited slip differential.

so it depends on the blend in the bottle, my understanding, and im sure ill be corrected if im wrong, is the 15's still have the G80 locker in the rear diff, which is designed to run without the addition of friction modifiers. If the fluid you purchased has a friction modifier pre blended into it, that might be causing the clutches to slip and make noise. That said, ive always run off the shelf standard gear oil and just not added any extra friction modifier and been fine. Can you describe the noise its making, grinding, clunking ect?

GMCdiesel 04-12-2019 05:26 PM

I don't think I have lockers or limited slip. Sounds similar to tire noise, it's not clicking noise.

269_Bob 04-12-2019 05:37 PM

I just pulled 4,000 miles with my 2019 2500hd pulling a 10,000lb trailer after changing to 75w140 Valvoline full synthetic. No problems, no noise.

jhplak325 04-12-2019 07:08 PM

Quote:

Originally Posted by GMCdiesel (Post 12145955)
I used 75w90. It's for limited slip differential.

Supposed to use full synthetic and no additives.

rockn69 04-12-2019 08:04 PM

Dmax diffs are lockers, not LS. Any CL-5 rated synthetic oil will work in them.


All times are GMT -7. The time now is 05:07 PM.

Powered by vBulletin® Copyright ©2000 - 2020, vBulletin Solutions, Inc.
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2020 DragonByte Technologies Ltd.
User Alert System provided by Advanced User Tagging (Pro) - vBulletin Mods & Addons Copyright © 2020 DragonByte Technologies Ltd.

 
For the best viewing experience please update your browser to Google Chrome