2005 Z-71 Rear Gear Oil

[hikerboy]

After searching and reading here, I'm just as confused as I was when I started. My '05 Z-71 with the G80 Eaton rear differential option has 50000 miles, thinking about changing the fluid (no drain plug on mine). It would appear that many have switched to Mobil 1 gear oil instead of forking over $30 a quart for the GM spec-d stuff....with no ill effects.....I tow a 4000lb trailer a few times a year, just wondered what the best option to go with is......$8.99 a quart for Mobil 1, or $30.00 for GM purple juice. Anyone with regrets not going with the GM stuff?

[Black02Silverado]

Make the switch to Mobil 1 fluid, no need to pay the high price of the GM oil.

[txab]

Make the switch to Mobil 1 fluid, no need to pay the high price of the GM oil.

+1

Or one of the several other proven synthetics

[blankey]

I used Mobil 1 when I replaced mine and haven't had any problems.

[sahls01gmc]

Anybody upgraded the diff cover while they were there?

 

I've been contemplating doing this to mine recently, and I was wondering if anyone upgraded diff covers to ones with drains, and even heat sinks for cooler temps. With trailering and plowing, every bit to cool it off would help, right?

 

 

James

[xsports33]

The first fluid change i did i also replace the cover with a Mag-Hytec Differential cover. It's pretty trick. And it keeps the fluid a cooler and holds a quart more, IIRC. Also, it's uses a rubber o-ring for a gasket. The fluid i used was RP 75W-140. Since then, i have replaced it with RL HeavyDuty Shookproof because of the loads my rig sees and the larger tires. When i first changed to the Mag-Hytec diff cover i noticed it helped keep the fluid cool when towing and general driving.

[sahls01gmc]

The first fluid change i did i also replace the cover with a Mag-Hytec Differential cover. It's pretty trick. And it keeps the fluid a cooler and holds a quart more, IIRC. Also, it's uses a rubber o-ring for a gasket. The fluid i used was RP 75W-140. Since then, i have replaced it with RL HeavyDuty Shookproof because of the loads my rig sees and the larger tires. When i first changed to the Mag-Hytec diff cover i noticed it helped keep the fluid cool when towing and general driving.

 

I looked up the one that would fit my truck, and it looks like it is a 12 bolt cover, but mine is a 14 bolt (I just counted! lol). The "2" bolts that seem to be missing are the top and bottom ones.....is this still the right one? Anyone know if it's a change that Mag-Hytech made....and it still won't leak?!?

 

 

 

James

[xsports33]

i would give them a call. They are really good with their customer service.