Can I use a lower VG? (cross posting, sorry)

[TurboFiat124]

Sorry for the cross post but figured this concerns hydraulic oil which is not normally used in a manual transmission in a car, I might get another perspective.

Here is my original post:

http://www.bobistheoilguy.com/forums/ubbthreads.php/topics/3594667/2

The transmission calls for a hydraulic oil VG 68 year round but below 50F the freewheel device has trouble engaging until the gearbox heats up. Supposably this is a sign that it's getting worn or weak.

I have experimented with different fluids and found the thinner the oil, the better it engages. Diesel fuel works best (no issues) and although an oil was never intended as a lubricant.

I was wondering if I were to use an AW 32 or even an AW 22 would this provide enough protection for the gears and bearings? The transmission probably never get's above 120F even in the middle of summer.

I can get AW 32 but have yet to find AW 22. Can you thin AW 68 with diesel fuel to obtain an AW 46 or AW 22 viscosity?

 

[MolaKule]

If it specifies an ISO 68 then a good ISO 46 such as Schaeffer's #254 should work fine. You're not exactly in Alaska.

Since an ISO 46 has about the same viscosity as an ATF, I would go any lower than that.

Salesrep on BITOG is a Schaeffer's sponsor.

Cutting it with diesel fuel is a no no because of the additives in diesel fuel.

Make sure your pump and spools aren't leaking internally.

 

[MolaKule]

Correction to above post:


Originally Posted By: MolaKule
If it specifies an ISO 68 then a good ISO 46 such as Schaeffer's #254 should work fine. You're not exactly in Alaska.

Since an ISO 46 has about the same viscosity as an ATF, I would NOT go any lower than that.

Salesrep on BITOG is a Schaeffer's sponsor.

Cutting it with diesel fuel is a no no because of the additives in diesel fuel.

Make sure your pump and spools aren't leaking internally.

 

[salesrep]

I think that MolaKule is spot on. Go down one viscosity and you will still have the benefits of a blended oil vs. diluting with fuel.

 

[supercity]

Try a HVI 46, it will be approximately the same visc as an ISO 68 at hotter temps