I have a 05 Chevy Silverado that has the rpo g80 that I need to do a service on bc the fluid looks bad and acts like it shudders while turning. What fluid does this take and I also heard there was a tsb on it does anyone have the tsb number
Need help
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Everything Ive read says 75/90 synthetic GL5 gear lube. Dark oil is from the clutches wearing and shutter could be from incorrect/contaminated/worn lube. I cant recall if you'll need to add a tube of friction modifier. Id say google it as you will read about 5 different oil level requirements. Couldent tell you which is correct however mine is pretty much coming out the fill hole but apparently GM used different heights on the fill plug on different years of some crapola like that.
2004 Sierra 3500 6.0L, auto, extended cab, cab&chassis, upgraded to 4wd
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Your owners manual has a pretty good list of what fluids to use and the approximate capacity. You can download it for free from gm's website.
Most people find not adding a friction modifier works fine, but a small portion of people seem to find they get some chatter with the g80, which goes away by adding a small amount of it.
Most people find not adding a friction modifier works fine, but a small portion of people seem to find they get some chatter with the g80, which goes away by adding a small amount of it.
From the '05 Owner's Manual (words in brackets are mine):
The proper level for the 1500 Series is from 5/8 inch to 1 5/8 inch (15 mm to 40 mm) below the bottom of the filler plug hole.
Use SAE 75W-90 Synthetic Axle Lubricant (GM Part No. U.S. 12378261, in Canada 10953455) meeting GM Specification 9986115. [no friction modifiers in this]
For steerable Rear Axel - Synthetic Axle Lubricant; use only GM Part No. U.S. 12378557, in Canada 88901362. Do not add friction modifier. [This is simply a 75W-90 with friction modifier already added]
The proper level for the 1500 Series is from 5/8 inch to 1 5/8 inch (15 mm to 40 mm) below the bottom of the filler plug hole.
Use SAE 75W-90 Synthetic Axle Lubricant (GM Part No. U.S. 12378261, in Canada 10953455) meeting GM Specification 9986115. [no friction modifiers in this]
For steerable Rear Axel - Synthetic Axle Lubricant; use only GM Part No. U.S. 12378557, in Canada 88901362. Do not add friction modifier. [This is simply a 75W-90 with friction modifier already added]
So should or should I not add the modifier
Ok thanks a lot. And I was reading on the tsb I found for have fluid contamination and it says to drain and fill with 80w90 tsb number 91-4-109
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If it doesn’t call for it in the manual you don’t need it it would have it in the fluids if it was needed 😎👍
True that
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