Rearend fluid
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You can get everything from a local auto parts store except the GM Rear End additive. You have to get that from a GM dealer (or maybe order online, but I've always just popped into the dealer).
GM Additive - $10.40
Felpro Rear End gasket - $5.14
2 qts. Mobil1 75w-90 - $19.98
Brakleen (to clean off the cover) - $2.79
With tax... Less than $40
Of course that was with the prices that my local auto parts store charged and all, but you get the idea.
Good luck fellow LS1 owner!
- Adam
GM Additive - $10.40
Felpro Rear End gasket - $5.14
2 qts. Mobil1 75w-90 - $19.98
Brakleen (to clean off the cover) - $2.79
With tax... Less than $40
Of course that was with the prices that my local auto parts store charged and all, but you get the idea.
Good luck fellow LS1 owner!
- Adam
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Ahhh... good deal. Well if you can pick up the additive from a parts store than go for it. Just make sure it's the real GM stuff... I have never seen it in a random chain auto parts store, so be weary... Make sure you get the right stuff for GM rear ends
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Also, twice now I've seen people saying to buy gasket, but when I asked the other day, most everyone said just use RTV silicone and be done.
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Yes autozone sells the additive and it states on the tube (GM 1052358)
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Auburn=additive needed
Torsen=no addtive bc there are no clutches in it.
Putting additive in a Torsen is a waste of money and just plain silly. If you have a torsen, buy cheap **** 75/90 gear oil and you're golden.
Torsen=no addtive bc there are no clutches in it.
Putting additive in a Torsen is a waste of money and just plain silly. If you have a torsen, buy cheap **** 75/90 gear oil and you're golden.
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I'd put in a 75w-140 gear oil. The higher viscosity index means it'll deal with heat a much better, as in not suffer from hi temp viscosity breakdown.
I can't imagine why anybody would recommend "cheap **** gear oil". If you wouldn't do such a thing to your engine, why would you do it to your rear end gears and bearings that see higher loads than your engine ever will?
I can't imagine why anybody would recommend "cheap **** gear oil". If you wouldn't do such a thing to your engine, why would you do it to your rear end gears and bearings that see higher loads than your engine ever will?
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I use 75w90,
to answer your gasket question, put a bead of rtv on the outside of the rear end housing, lightly press on your $3 gasket, then put a bead of rtv on rear end cover, press it on the gasket and start tightening the bolts evenly. I've never had a leak doing it this way.
to answer your gasket question, put a bead of rtv on the outside of the rear end housing, lightly press on your $3 gasket, then put a bead of rtv on rear end cover, press it on the gasket and start tightening the bolts evenly. I've never had a leak doing it this way.
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I know you only need additive when there are clutches. My question was actually, doesn't someone else make an additive besides GM since this is not a GM unit, it's an auburn unit. I know GM additive will work but just asking. Sorry, not an expert on rearends. Thanks for the info on gasket. That's actually what I usually do on most gaskets, or none at all with just gasket, but I like the added insurance.
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I know you only need additive when there are clutches. My question was actually, doesn't someone else make an additive besides GM since this is not a GM unit, it's an auburn unit. I know GM additive will work but just asking. Sorry, not an expert on rearends. Thanks for the info on gasket. That's actually what I usually do on most gaskets, or none at all with just gasket, but I like the added insurance.
To fleet manager, following normal services intervals, any gear oil you find on the shelf with be sufficient. Hence my recommendation of the cheap ****, thats what the rear end is designed to run.
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As the point contact loading on a single gear tooth can reach 1 million psi under the right circumstances, and cheap oils are MUCH more prone to shear breakdown than good ones are due to their increased additive contents, I'd use the good stuff here too. You've got a car that you spent thousands to buy, and in some cases have spent additional thousands on with upgrades. Many have $3 grand or so just in the rear end. Seems like cheaping out on the oil you put in that rear end is a really serious case of being penny wise and pound foolish. We're talking what, maybe a $50-$60 dollar difference to better protect your investment.
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Yes Auburn makes its own additive. It comes when you purchase a new posi unit. I have seen bottles of it for sale on ebay, but other then that I dont know where you would get it.
To fleet manager, following normal services intervals, any gear oil you find on the shelf with be sufficient. Hence my recommendation of the cheap ****, thats what the rear end is designed to run.
To fleet manager, following normal services intervals, any gear oil you find on the shelf with be sufficient. Hence my recommendation of the cheap ****, thats what the rear end is designed to run.
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Using that logic, it makes perfect sense to run the absolute cheapest re-refined house brand motor oil you can buy as long as it has the API star and is the correct viscosity.
As the point contact loading on a single gear tooth can reach 1 million psi under the right circumstances, and cheap oils are MUCH more prone to shear breakdown than good ones are due to their increased additive contents, I'd use the good stuff here too. You've got a car that you spent thousands to buy, and in some cases have spent additional thousands on with upgrades. Many have $3 grand or so just in the rear end. Seems like cheaping out on the oil you put in that rear end is a really serious case of being penny wise and pound foolish. We're talking what, maybe a $50-$60 dollar difference to better protect your investment.
As the point contact loading on a single gear tooth can reach 1 million psi under the right circumstances, and cheap oils are MUCH more prone to shear breakdown than good ones are due to their increased additive contents, I'd use the good stuff here too. You've got a car that you spent thousands to buy, and in some cases have spent additional thousands on with upgrades. Many have $3 grand or so just in the rear end. Seems like cheaping out on the oil you put in that rear end is a really serious case of being penny wise and pound foolish. We're talking what, maybe a $50-$60 dollar difference to better protect your investment.