Well my 2008 CTS (3.6DI) just turned 202k miles on the original diff fluid and trans fluids. I been meaning to change em both out since like 80k miles LOL! So I guess that OEM fluid has proven to be robust. I really am gonna change the diff and trans this month some time.
Rear Differential Gear Oil Comparison?
- Thread starter DR1
- Start date
Talk about procrastinating
Talk about procrastinating
I sold my 99 1/2 gmc 2500 to a friend when it had 225,000 miles on it, with the original diff oil. Probably still has it, knowing him.
Something indicates to me that many of you may be over maintaining your differentials or just doing it as a hobby:
From Dana/Spicer (heavy truck) warranty booklet:
Dana Recommends the Use of Spicer approved Lubricants for Extended Drain
Use the chart to locate the correct lubricant and change interval.
Note: See the line haul and vocational definitions for more information.
From Dana/Spicer (heavy truck) warranty booklet:
Dana Recommends the Use of Spicer approved Lubricants for Extended Drain
Use the chart to locate the correct lubricant and change interval.
Note: See the line haul and vocational definitions for more information.
| Synthetic or Mineral | Lubricant | SAE | Change Interval for Line Haul | Change Interval for Voca- tional |
| Synthetic | SHAES 256 Rev C | SAE 75W-90 | 500,000 miles [800,000 Km] or 3 years | |
| Synthetic | SHAES 256 Rev C | SAE 75W-90, SAE 80W-140 | 120,000 miles [193,000 Km] or 1 year | |
| Mineral | MIL-L-2105E/J-2360, API GL-5 Gear Oil, MIL- PRF-2105E | 75W, 75W-80, 75W-140 | 120,000 miles [193,000 Km] or 1 year | 60,000 miles [96,500 Km] or 1 year |
Looking at the owners manuals for 3/4 ton Chevy trucks, changing the differential fluid is not a required maintenance technique. It wasn’t in 2008, and it’s still not in 2020. 
D
Deleted member 89374
#neverchangethegearoilinthediffsLooking at the owners manuals for 3/4 ton Chevy trucks, changing the differential fluid is not a required maintenance technique. It wasn’t in 2008, and it’s still not in 2020.
Look at the calendar interval.... I think they are concerned about moisture and oxidation.
Depending on the exact ASTM test, it may very well be realistic for gear oil. Assuming of course the statistical analysis described in the test is followed for proper data presentation.
My brother has 560,000km on his 2007 Mercedes E220cdi and original differential fluid. He did 2 transmission refreshments and filter changes.
My old RAV4 made it over 300,000 miles on the factory fill.
- Joined
- Dec 30, 2006
- Messages
- 29,558
Absolutely!
- Joined
- Dec 30, 2006
- Messages
- 29,558
I also spent some time looking at the rear diff uoas here as well with Severe Gear having the lowest wear metals.
- Joined
- Dec 27, 2020
- Messages
- 199
Had my auto serviced last year. The shop owner checked my diff oil and said “oh it’s just been changed”. It did look new. Didn’t have the heart to tell him it was Amsoil Severe Gear 75W-110 and had 80,000+ kms on it. Custom 4-pinion LSD regularly used for reasonably heavy towing.
Sam_Julier
$50 Site Donor 2024
I use the least expensive lube that meets the SAE- J2360 or MIL PRF 2105 specification at the manufacturer‘s reccomended viscosity.
Brand is irrelevant to me.
Brand is irrelevant to me.
Sam_Julier
$50 Site Donor 2024
So do lots of 80W90 conventional lubes: Mobil HD, Castrol Axle, Valvoline HD, Shell Spirax HD, etc.
Similar threads
