help me pick some oil for my rebuilt tranny

[Judgeman]

so i just finished rebuilding a E153 transaxl for my 91 mr2, i put all new bearings, all new syncrose and a used Kaaz 2way lsd in it.

the problem im having is kaaz says dont use synthetic oil.

http://www.kaazusa.com/techhelp2.html

i wont to use the best oil i can get for my new transmission but thay all seem to be synthetic.

should i just ignore this and use a good synthetic anyway or what?

 

[d00df00d]

The operative term here is "smooth". Any decent GL-5 rated oil will handle the stress, synthetic or not, but smooth operation requires very carefully balanced friction characteristics -- for example, if it's too slippery, you might get chatter. I can only imagine that balance would be easier to achieve with a dino oil. Maybe Kaaz insists on not using synthetics because there are too many synthetics that wouldn't work.

I can't imagine such an oil doesn't exist, though, and synthetic oil is always nice to have in any high stress application. I would do a lot of homework to find an appropriately LSD-friendly synthetic: read a LOT of reviews on forums and such, and see what others are using in their tight 2-way diffs. Make sure to get a lot of opinions from a variety of sources, applications, and levels of technical expertise.

 

[mechtech2]

I don't think the synthetic will cause wear or harm, but may allow that type of LS to slip or chatter under certain conditions.
Give any fluid 1-500 miles before condemning it in this area, though.
I would go with a synthetic and take that chance, but that's me.

 

[Judgeman]

thanks for the input.
a guy on the MR2 forums sed amsoil svg worked great for his kaaz dif but his old syncrose didnt work so well with it.
i also found that redline has some gear oil juust for LSDs.
i guess i still got sum thinking to do.

 

[mechtech2]

Get a hold of 'PABLO' on this site.
He is an expert about Amsoil products and can get them to you quickly.

 

[d00df00d]

There are plenty of gear oils with additive packages designed for LSDs. Red Line and Amsoil aren't the only ones.

 

[unDummy]

The LSD and manual share the same fluid, right?

You'll have to pick a fluid that balances shift feel with LSD feel. Trial and error with lots of driving will be needed.

 

[Judgeman]

^^ yes thay will be sharing the same oil, both kaaz and toyota say to use 75-90 gl-5 im just trying to get some more info on what type and brand i should consider befor i put my transmission in.

 

[gtx510]

Why not run a VOA of Kaaz gear oil? http://www.kaazusa.com/oil.html

I don't see why you couldn't use a synthetic gear oil. I'd look for GL-4/5 75w90's that don't contain moly to keep the synchros happy. Amsoil SVG, Motul Gear 300, etc.

 

[Judgeman]

at $45 a can tha kaaz oil is a litle pricy, pluss its somthing i have to order rather then just go pick up.

 

[unDummy]

Give RoyalPurple a try. Its Gl4/Gl5 rated and seems to be a decent balance between LSD chatter prevention, along with making the synchros work.
I know several that have used Amsoil SVG and Mobil1 75w90 with excellent shift quality with various transmissions. So, there are other GL5 gear oils that could possibly work.

 

[Bror Jace]

Judgeman, I'd use just about any GL4/GL5 oil ... and change it after 2,000-3,000 miles. Break-in debris is probably gonna be considerable.

I'd even try Coastal (Advance Auto Parts sells it, I think) 75W-95. which I think is rated GL3/4/5 and MT-1. After all, you should be babying this thing for the first thousand miles.

Let it break-in ... then go for the pricey/exotic stuff.