Redline Synthetic Gear Oil

[John M.]

Can someone give me some help on which type is used for the transmission and which for the differential. Their website is a little confusing. This will be a street driven Corvette. Thanks

[Rick A.]

Re: Redline Synthetic Gear Oil

I use MT-90 for both the manual xmsn and the transaxle in my 1963

[Wayne K.]

Re: Redline Synthetic Gear Oil-Does it .......

really make a difference in the way the transmission shifts when the transmission is up to operating temperature. I've tried other synthetics in a Jeep I had and I couldn't tell any difference. Would like some imput on this. Thanks.

[Duke W.]

Re: Redline Synthetic Gear Oil

The GM requirement for both the gearbox and diff. oils is Mil-L-2105, which is equivalent to 80W-90 GL-5; plus if you have a positraction axle you must use an anti-chatter additive.

Redline has two applicable gear oil products, 75W-90 and 75W-90NS. According to their literature and web site, the 75W-90 contains the anti-chatter additive for limited slip differentials and can be used in such differentials without supplemental additives.

75W-90NS DOES NOT contain the anti-chatter additive, so it is suitable for vintage Corvette manual transmissions. Using a gear oil with the anti-chatter additive in a manual transmission may have an adverse effect on synchronizer function.

MT-90 is a 75W-90 GL-4 gear oil, so it does not meet the original Mil-L-2105 spec. MTL is a 70W-75 GL-4 and is specifically designed for manual transmissions that originally specified ATF as the lubricant.

You can find out more about motor oil and gear oil specifications at the American Petroleum Institute Web site: www.api.org

Duke

[John M.]

Re: Redline Synthetic Gear Oil

Thank you very much for the responses guys. Ill check out that website, too.
John

[Gene M.]

Re: Redline Synthetic Gear Oil

Many of the rebuild articals do not advise using synthetics in muncies. I have always used the recommended standard lubricants, they have lasted in use for the first thirty plus years why not now?.

[Scott Marzahl]

Re: Redline Synthetic Gear Oil

I thought about using RedLine or Amsoil in my Muncie I just rebuilt too. I've read conflicting things regarding synthetics in the Muncies like the syncro's do not like synthetic, it's too slippery etc. So I called three different Muncie rebuilders, they all told me to stick with the regular Dino gear oil. I would like to hear from guys who have run both or checked out their tranny after running synthetic gear oil.

[John M.]

Re: Redline Synthetic Gear Oil

Hey Scott, I went to the general store in my little town of 900 people and there on the shelf was a 90 weight GL5 gear oil, exactly what was recommended by GM. Makes me wonder why I worry so much about a car that is driven with care on sunny days only!

[Tom R.]

Re: Redline Synthetic Gear Oil-Does it .......

I'm about to change differential fluid and gasket in my 78 and picked up the Red Line "Limited-Slip Differential" and my mechanic suggested I stick with the GM differential fluid. I was surprised so this thread is instructive.