Best differential fluids???????
Thread Starter
Melting Slicks
Joined: Nov 2004
Posts: 2,275
Likes: 5
From: Lake Oswego, Near Portland Oregon
Best differential fluids???????
Going to dump and replace differential oil and additive to see if it helps with the groaning clutch plates in the differential...looking for opinions on best fluids for replacement,....Red Line, Lucas, or ?? Best limited slip clutch additive, GM or specialty maker????
What are you autocross or road circuit racers using these days for high reliability?
Hoping to do this over the weekend, so will need to buy whatever I get by Friday afternoon..
Thanks in advance!!!
Jennifer
What are you autocross or road circuit racers using these days for high reliability?
Hoping to do this over the weekend, so will need to buy whatever I get by Friday afternoon..
Thanks in advance!!!
Jennifer
Last edited by FiberglassFan; Jun 29, 2010 at 04:12 PM.
Melting Slicks
Joined: Sep 2005
Posts: 2,568
Likes: 264
From: Near Charlotte NC
Know one knows what is best.
I use Amsoil Severe Gear 75-90 in my 02Z diff and 03 S2000 diff.This forum vendor is a trusted supplier of Amsoil.
http://www.c66racing-synthetics.com/
As always,IMO.
\db2
Carolina
I use Amsoil Severe Gear 75-90 in my 02Z diff and 03 S2000 diff.This forum vendor is a trusted supplier of Amsoil.
http://www.c66racing-synthetics.com/
As always,IMO.
\db2
Carolina
Burning Brakes
Joined: Aug 2005
Posts: 772
Likes: 6
From: Huntsville AL
I use the Mobil 1 75w90 LS. It already has the Limited Slip additive in it. Price is $8.99 a quart at Autozone. You will need 2 quarts.
Or you can go with Royal Purple 75w90. It too has the additive already in it. But it will cost more. Not sure it will give you any better results.
Personally, I would go with Mobil 1.
And there is enough room behind the diff to put a piece of hose on the end of the bottle and pour it in. Won't need a pump.
Or you can go with Royal Purple 75w90. It too has the additive already in it. But it will cost more. Not sure it will give you any better results.
Personally, I would go with Mobil 1.
And there is enough room behind the diff to put a piece of hose on the end of the bottle and pour it in. Won't need a pump.
Race Director
Joined: Mar 2001
Posts: 11,405
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From: Whippany NJ
CI 6-7-8-9 Veteran
St. Jude Donor '08-'09
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Le Mans Master
Joined: Dec 2008
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From: Texas
I use the Mobil 1 75w90 LS. It already has the Limited Slip additive in it. Price is $8.99 a quart at Autozone. You will need 2 quarts.
Or you can go with Royal Purple 75w90. It too has the additive already in it. But it will cost more. Not sure it will give you any better results.
Personally, I would go with Mobil 1.
And there is enough room behind the diff to put a piece of hose on the end of the bottle and pour it in. Won't need a pump.
Or you can go with Royal Purple 75w90. It too has the additive already in it. But it will cost more. Not sure it will give you any better results.
Personally, I would go with Mobil 1.
And there is enough room behind the diff to put a piece of hose on the end of the bottle and pour it in. Won't need a pump.
Burning Brakes
Joined: Feb 2008
Posts: 1,228
Likes: 9
From: Crossville TN
Know one knows what is best.
I use Amsoil Severe Gear 75-90 in my 02Z diff and 03 S2000 diff.This forum vendor is a trusted supplier of Amsoil.
http://www.c66racing-synthetics.com/
As always,IMO.
\db2
Carolina
I use Amsoil Severe Gear 75-90 in my 02Z diff and 03 S2000 diff.This forum vendor is a trusted supplier of Amsoil.
http://www.c66racing-synthetics.com/
As always,IMO.
\db2
Carolina
Team Owner
Joined: Mar 1999
Posts: 22,025
Likes: 192
From: At the beach in little Rhody
Depends on the differential. DTE has their own requirements and likely other aftermarket vendors as well. I used Amsoil until my DTE unit was installed and now I use the required fluid from DTE which is Redline 75W-140 with double additive.
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Thread Starter
Melting Slicks
Joined: Nov 2004
Posts: 2,275
Likes: 5
From: Lake Oswego, Near Portland Oregon
I think I'll go for the Mobil 1....I can get it locally FAST, and as has the additive pre-blended then I don't need another visit to the stealership for that. I can also get RedLine locally, but I am already using Mobil 1 in the engine, and the parts dealer where I buy Mobil 1 and Wix filters are a decent and helpful shop, 
cool people, so I'll give them my business. I did check up on the Amsoil, and it looks like really good stuff, but I can't get it locally-quickly. RedLine is stocked across town,
adds about an hour round trip compared to 12 minutes or less for my Mobil 1 supplier...
Thanks for all the suggestions.....I did NOT know that Mobil 1 had a fluid for this application, ....very helpful info, THANKS to everyone for chiming in....!!!
Jennifer
cool people, so I'll give them my business. I did check up on the Amsoil, and it looks like really good stuff, but I can't get it locally-quickly. RedLine is stocked across town, adds about an hour round trip compared to 12 minutes or less for my Mobil 1 supplier...Thanks for all the suggestions.....I did NOT know that Mobil 1 had a fluid for this application, ....very helpful info, THANKS to everyone for chiming in....!!!
Jennifer
Thread Starter
Melting Slicks
Joined: Nov 2004
Posts: 2,275
Likes: 5
From: Lake Oswego, Near Portland Oregon
Went to my regular Mobil 1 dealer to get the diff lube, and they don't carry it!!!, ..all the motor oils, and non of the gear oils...BUT they NOW have every type of RedLine diff fluid in stock, so I didn't have to cross town for that brand..got some with the LS additive and did the deed...
NO MORE GRUNTING from the DIFF!!!
The old fluid that came out was clear and slippery, no grit, no weird haziness....but after 70k miles
it must have started to loose whatever it is the clutch plates like...
Differential problem fixed, .....but I did see a lot of grungy build-up under the general rear end area...
...looks like I have a trickle leak on one of the ATF seals to deal with, likely at or near the back of the transmission where it bolts up to the diff....I'll have to go the shop for the ATF top-up and inspection, as that is one step beyond our driveway wrenching
Jennifer..
NO MORE GRUNTING from the DIFF!!!
The old fluid that came out was clear and slippery, no grit, no weird haziness....but after 70k miles
it must have started to loose whatever it is the clutch plates like...Differential problem fixed, .....but I did see a lot of grungy build-up under the general rear end area...
...looks like I have a trickle leak on one of the ATF seals to deal with, likely at or near the back of the transmission where it bolts up to the diff....I'll have to go the shop for the ATF top-up and inspection, as that is one step beyond our driveway wrenchingJennifer..
Last edited by FiberglassFan; Jun 30, 2010 at 10:43 PM.
Team Owner
Joined: Mar 1999
Posts: 22,025
Likes: 192
From: At the beach in little Rhody
Not sure which Redline fluid you bought. There is 75W-90 which has the additive in it (4% as I recall) and then there is the 75W-90NS which does not have the additive. If you bought the 75W-90 and installed more additive you may have too much additive and eliminated the limited slip capability of the clutches in the differential. Not sure if this is what you did but just wanted to let you know.
Thread Starter
Melting Slicks
Joined: Nov 2004
Posts: 2,275
Likes: 5
From: Lake Oswego, Near Portland Oregon
We got the non-NS....with the additive already mixed.
Nothing extra added or needed, which was nice not having to deal with the small bottles of stinky GM additive stuff....
Thanks for checking! Good to have folks on the '6'
Jennifer
Nothing extra added or needed, which was nice not having to deal with the small bottles of stinky GM additive stuff....
Thanks for checking! Good to have folks on the '6'
Jennifer
Burning Brakes
Joined: Aug 2005
Posts: 772
Likes: 6
From: Huntsville AL
Before you decide it is the transmission leaking, make sure it is not the differential drivers side cover seal problem. The housing was not machined properly and the seal can leak. It is a drivers side only issue. Do a search and you will find all the info on it. I just posted the process a few days ago.
Thread Starter
Melting Slicks
Joined: Nov 2004
Posts: 2,275
Likes: 5
From: Lake Oswego, Near Portland Oregon
Good idea! I am about to have the tranny fluid checked later this afternoon just to make sure....Over the weekend we'll jack up the car and dose the area with degreaser, and after a good soaking, pressure wash off all the gunk....Once it is clean, it will be a tad easier to spot the leakage point...Right now it is just COVERED in filth so bad that you cannot tell anything about the leak source, and the rear of the trans and the whole underside of the diff are coated in oily dirty black gunk...this greasy gunk 'sorta' smells like ATF, but it also sorta smells like gear oil...not enough of a smell signature to help me decide...First I just want to make sure that I do not have a low ATF situation, and then we'll move forward to cleaning and leak detection....Thanks for the tip! I was not specifically aware of the diff drivers side seal issue....Now I see it is common! 
Jennifer
for the tip! I was not specifically aware of the diff drivers side seal issue....Now I see it is common! Jennifer
