Question... On my 84 truck, all the manuals call for gl-4 gear oil in the tyranny. I called the two dealers since I can't find it at the local parts stores and they told me to use gl-5 because that is what they would use. Should I just order some Redline MT-90 and be done with it? If so, does anyone have a good source for it?

 

Yes Mt-90. Amazon is about the best place to find it.

 

x2 Just ordered some off Amazon, you can find better prices but with Amazon you get free shipping so it turns out to be the cheapest

 

You might check Redline's dealer list and see if there is a local source. I once found a local race shop that carried it and sold it for less than on-line if I picked up a case of the stuff.

Have also found conventional GL4 oil at local auto parts stores. Usually StaLube brand in a gallon jug.

 

Used MT-90 that I ordered from Summit. They carry gallon size containers.

 

Thanks for all the info. I am going to order online since there are no dealers close by.

 

Ive used 80-90w before and had hard shifting problems when col 70-90w fixed the problems they both say gl3 gl4 and gl5 compatible but their is a differance in shifting when col if you have problems might depend on mileage on tranny to

 

80-90 mobil 1 synthetic.. pick it up anywhere works fine

i use dino valvoline in my tranny/case/axles ive run synethetic thru my transmissions before and others ... its all mental to me