what kind of tranny and rear end oil

[n1gzd_plymouth]

I have a 36 plymouth with 230 CI engine and probably stock rear end and transmission (for now I am assumging that).

The book says that for tranny and steering gearbox I should use:

SAE 90 FLUID GEAR LUBRICANT (LOW COLD TEST)

and the book says that for rear end I should use:

SAE 90 EXTREME PRESSURE HYPOID GEAR LUBRICANT (LOW COLD TEST)

Can someone please translate these two things into what modern available products I should use.

Thanks,

Rebecca

[greg g]

extreme pressure refers to the lube needed for rear end gears as the gears eed meshing protection between their faces and also lubrication for the sliding as they spriral past one wother during engagement. Transmissions although these days the gears are angled do not have the sliding loads, so the high pressure lube is not necessary. That said I don't there would be a problem using the diffy rated oil in the trans. Where as trans lube would not provide the needed for diffy.

Smarter folks may disagree, ad I would hope they would do so here.

[n1gzd_plymouth]

ok. so I think that I understand that you think that I can use the 90 weight differential oil that I already bought (very common stuff) for both of these oils (my diffy, my tranny and my steering gear box).

Thanks,

Rebecca

[Plymouthy Adams]

NO...hypoid oil of the 80/90W has special additives that are there for the protection against shear...the tranny and sterring 80w gear oil does not need this additive...there is a big difference between gear oil and hypoid oil..other that the above mentioned additives, the viscosity of the gear oil is consistant to about a 40 wt motor oil...(per oil related web site)

[n1gzd_plymouth]

ok. so I should be ok with rear end 90W gearbox oil but I need to find some other 90W gear oil for my tranny and steering box. Hopefully it will be obvious which product to buy when I am in the store (general gearbox oil but not for rear end).

Thanks,

Rebecca