What brand of gear oil do you prefer?

Hey Guys,

I'm getting ready to replace all my wheel bearing and in the process I'll need to change the rear differential gear oil. I believe I need to use 80-90w gear oil though I haven't confirmed with my Service manual yet. I have 3.23 open differential, so I don't need the posi additive. Since this is my first time ever changing gear oil I'm not sure what brand I should use? Does anybody want to weigh in on their recommended brand and why they prefer it?

Thanks fellow enthusiasts

I really don't have a preference when it comes to gear oil, just as long as it meets the requirements of an 80W-90 fluid with a GL-5 rating.

Shawn,I have been using Castrol GTX in all my cars and bikes for over 30 years with no problems.
Just make sure you clean the magnet and the housing out good just in case there are any fine
metal shards present.Brake cleen works well as long as you let it dry completely before sealing
the housing back up.

I'm with GMTECH any 80-90 with GL5 rating. I use autozone Costal brand. I have a 9C1 sedan with posi. I use the same oil with limited slip addative.


Randy

Shawn:

When you have both axles out, carefully clean out the axle tubes and carrier with solvent. Better yet, brake cleaner. If your bearings are bad, be even more careful. Ended up having to replace the entire rear gear set after a bearing job because I was rushed and didn't clean up the internals well enough. A $500 lesson in "there's no such thing as good enough".

Heard good things about synthetic gear oils but have used named brand oils for 40 years and never had a problem. A few bad bearings and seals but no failures (with the exception of the above incident).

Bill

Is there a echo in here?

Flasheroo wrote:

Is there a echo in here?

Can't be stressed enough.

Bill

I use Lucas 80-90...just like Lucas products personally. Just put some in yesterday with my rear end rebuild. Bill is right about the cleaning too. Mineral Spirits work well (or brake cleaner)

Chris

I've always been on gmtech's boat, using whatever 80/90 the parts store has. Name and house on different occaisions. I see you have an open rear, but have read stories about synth a posi not playing nice.

Chris your buddy that put your gears in had a beautiful garage and spotless as well.Now he got your housing looking like it had just been built.

Thanks for the input people. I will most likely use supertech brand from wally world. I just wasn't sure if the benefit is worth the cost to switch to a synthetic or high dollar name that's available.

I plan to clean thoroughly. I'm pretty sure that there is no catastrophic damage but I won't know for sure until I open her up. She still drives and all, and this was all the result of a loud deep resonance that starts up around 75MPH. I took it to a shop and they recommended replacing all four sets of bearings. Well their quote was over $500.00 bucks so I politely declined and started pricing parts and tools. Even with buying the tools I should need to add to my stash I'll spend less than half what they quoted. If I did the loan a tool program I could get away with less than $120.00, but I want some new tools. I like to get dirty working on cars, and I'm looking forward to getting Ms. Roadie up on stands again. I just need to finish up my van's repairs before I can start working on Ms. Roadie again. Wifes orders ya know. Anyway this weekend I was able to completely flush the brake system, repack the front bearings, turn the front rotors, replace all the shocks, flush/replace the rear differential fluid and gasket, and get an oil change on the green giant (that's what the wifey calls our van, GMC Savanah High top conversion by Tiara motor coach). I wonder if he qualifies as a long roof? I could post pics if'n you guys want me too. I still have to replace the fuel filter and change out the water pump before he's finished. Then I can start on Ms. roadies bearings.

MORE TOOLS BETTER!