What gear lube to use?
Thread Starter
Racer
Joined: Sep 2009
Posts: 416
Likes: 1
From: Owego NY
What gear lube to use?
Hey guys I don't have my book with me to tell me what gear lube I should be running in the rear end. I plan on stopping after work to buy some. What are you guys running?
Le Mans Master
Joined: Oct 2007
Posts: 9,680
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From: Akron Ohio
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Remember not all fluids have the limited slip additive in them. Either pick some up with the oil or get a fluid that has additive in it.I use the AMSOIL Severe Gear 75W-90 in mine which includes the additive. All I did was put the fluid in and have had zero issues with chattering tires.
http://kahunamotorsports.com/svg-product-page.html
If you do add additive, make sure to drive in figure 8s in a parking lot to make sure it mixes in well and gets to the clutches quicker.
Le Mans Master
Joined: May 2004
Posts: 5,378
Likes: 531
I'm running into this issue as well with a D44 I'm replacing fluid in soon. It's not rocket science but one tends to make it such when you see all the choices for fluid available.
Local Car Quest parts store has Royal Purple 75W-90 which is listed with additive. Also, the diff requires 1.5 quarts of fluid gear fluid plus additive correct?
Local GM dealer told me one container of gear fluid plus three bottles of slip additive. I did some reading on the forum and see two 23 ounce bottles of GM 80w-90 gear lube and one bottle of slip additive.
Pro/Cons of using Royal Purple 75w-90? 80w-90 is what I see used the most so far.
Local Car Quest parts store has Royal Purple 75W-90 which is listed with additive. Also, the diff requires 1.5 quarts of fluid gear fluid plus additive correct?
Local GM dealer told me one container of gear fluid plus three bottles of slip additive. I did some reading on the forum and see two 23 ounce bottles of GM 80w-90 gear lube and one bottle of slip additive.
Pro/Cons of using Royal Purple 75w-90? 80w-90 is what I see used the most so far.
Le Mans Master
Joined: Oct 2007
Posts: 9,680
Likes: 3,427
From: Akron Ohio
2025 Corvette of the Year Finalist - Modified
2024 C5 of the Year Winner - Modified
2023 C5 of the Year Finalist - Modified
2022 C5 of the Year Finalist - Modified
St. Jude Donor '09-'10-'11
I'm running into this issue as well with a D44 I'm replacing fluid in soon. It's not rocket science but one tends to make it such when you see all the choices for fluid available.
Local Car Quest parts store has Royal Purple 75W-90 which is listed with additive. Also, the diff requires 1.5 quarts of fluid gear fluid plus additive correct?
Local GM dealer told me one container of gear fluid plus three bottles of slip additive. I did some reading on the forum and see two 23 ounce bottles of GM 80w-90 gear lube and one bottle of slip additive.
Pro/Cons of using Royal Purple 75w-90? 80w-90 is what I see used the most so far.
Local Car Quest parts store has Royal Purple 75W-90 which is listed with additive. Also, the diff requires 1.5 quarts of fluid gear fluid plus additive correct?
Local GM dealer told me one container of gear fluid plus three bottles of slip additive. I did some reading on the forum and see two 23 ounce bottles of GM 80w-90 gear lube and one bottle of slip additive.
Pro/Cons of using Royal Purple 75w-90? 80w-90 is what I see used the most so far.
The second number is what is more important. You could put in straight 90 weight oil but it would be much thicker in the cold. I dont think you will notice a difference between 75W or 80W oil.
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Le Mans Master
Joined: May 2004
Posts: 5,378
Likes: 531
The plan was to lay it flat on the garage floor tomorrow with the drain plug off until Royal Purple comes spilling out during adding. The drain plug has the classic signs of vice grip bite marks all over it.
I'm using high temp red silicone gasket material, same stuff used for oil pans and valve covers.
Slingshot
Joined: Dec 2001
Posts: 3,817
Likes: 24
From: Charlotte NC
Well, I picked up two quarts of Royal Purple Max-Gear 75W-90 with Synerlec. I'm assuming Synerlec is the slip additive. I won't be filling the D44 today, I just finished cleaning off the surfaces to seal the batwing back to the differential again.
The plan was to lay it flat on the garage floor tomorrow with the drain plug off until Royal Purple comes spilling out during adding. The drain plug has the classic signs of vice grip bite marks all over it.
I'm using high temp red silicone gasket material, same stuff used for oil pans and valve covers.
The plan was to lay it flat on the garage floor tomorrow with the drain plug off until Royal Purple comes spilling out during adding. The drain plug has the classic signs of vice grip bite marks all over it.
I'm using high temp red silicone gasket material, same stuff used for oil pans and valve covers.
FWIW - my experience has been very positive.
Le Mans Master
Joined: May 2004
Posts: 5,378
Likes: 531
I have used Royal Purple gear oil in my Dana 44 differential and my Super T-10 tranny for several years now. I personally spoke to one of the tech specialists at Royal Purple HQ in Texas and he assured me that I did not need the limited slip additive when using Royal Purple gear oil. Sooooo, I did not add anything to the trans or the differential other then the Royal Purple gear oil. I have had no ill effects what so ever. What's more, my transmission shifts much smoother, is significantly quieter and no longer pops out of 2nd gear when decellerating down a hill.
FWIW - my experience has been very positive.
FWIW - my experience has been very positive.
When the drain hole starts to spill fluid leave it at that? I thought about plugging the hole then adding a little extra for good measure. I've always been terrible at the simplest things like sealing and filling.
Slingshot
Joined: Dec 2001
Posts: 3,817
Likes: 24
From: Charlotte NC
