Could I use this in my transmission as well as differential on a '77 5spd? I know everybody runs Redline but this has to be close in quality and is a 1/3rd of the price. http://www.walmart.com/ip/Super-Tech-75W-90-Syn-Blend-Gear-Oil-1-Quart/16795248

It's might be OK, but I'd do some serious homework on the quality of the oil before putting it in my car.

A transmission rebuild costs about $1,000, and I "know" Redline is a good product...

I am not familiar with that brand. It has the GL-5 rating so it SHOULD be ok. I would be more comfortable with a recognized brand of conventional oil such as Valvoline or Castrol.

I really don't know. But considering that you do not need to change the oil very often are you really saving that much money?

1/3 the price? So what? I replace my fluids once every few years at most. What's another $10?

Could I use this in my transmission as well as differential on a '77 5spd? I know everybody runs Redline but this has to be close in quality and is a 1/3rd of the price. http://www.walmart.com/ip/Super-Tech-75W-90-Syn-Blend-Gear-Oil-1-Quart/16795248

Differential yes, transmission NO!!!

GL-5 oils have too much sulfur with will destroy the brass/bronze synchronizers in the transmission. The transmission requires GL-4 gear oil. Redline MT-90 works, and there is a Penzoil product that will work. Look for a reference to "safe for Yellow Metals" in the description on the container.

Yeah I guess I am being a cheapskate on this for some reason. I've done too much work and thrown money around like crazy. I'll go with Redline products. Thanks for your replies.

If you don't have a Redline Dealer and you don't want to order it - - you can also use Royal Purple Max-Gear. Many of the National auto parts stores carry it in local stock. It is a few more bucks - but I don't like waiting of stuff to be shipped..

http://www.royalpurple.com/product-categories/automotive/#!max-gear

GL-4 & GL-5 .. safe for yellow metals.. etc.

FWIW

Carl B.