Synthetic gear oil

[Bobo]

Is there a rule of thumb regarding the interval for changing synthetic transaxle gear oil?. I have a 95SE 5-speed and just got the transmission rebuilt. I didn't go with Redline MT-90 because of its lack of availability where I am. They used Castrol 75w90 GL4 synthetic.

Regular gear oil should be replaced about every 30,000 miles. I know the owner's manual doesn't specify a replacement interval and I didn't have my first change until about 56,000 miles. I was told that I should have had it changed long before then because of its color - jet black.

[PetitFrereMaxima]

Hey, talk to this guy, talkinghorse. I think he can give you some good insight about this. PM him. Look him up and pm him. He is knowledgeable and can give you some good advice. Up to you if you take it or not.

[Bobo]

Talking Horse markets Amsoil products. I already have Castro in place. Perhaps he could shed some light on the relative change intervals.

Thanks

[OOmaxSE]

Changing should be roughly 60k. I just put in MT-90 at $10 a qt and this thing is like WATER! Incredible for our tranny, very smooth.

[Love_00_Max]

Thumb rule use syn, I use Amsoil SV gear fluids in my highlander.

Capacity of unit vs change interval.

1Q - 30K miles
2Q - 45K miles
3Q - 60K miles

[talkinghorse]

Originally Posted by Love_00_Max

Thumb rule use syn, I use Amsoil SV gear fluids in my highlander.

Capacity of unit vs change interval.

1Q - 30K miles
2Q - 45K miles
3Q - 60K miles

I've not seen the capacity/change interval rule of thumb before.

For differential applications, AMSOIL SV(X) is recommended for up to 100K drain intervals in normal service or 50K in severe service. In non-differential applications follow OEM change recommendations....if no service interval is specified AMSOIL Severe Gear can be used twice as long as petroleum gear oils.

The synthetic GL-4 Manual Transmisson gear oil I sell so much of to our members will provide twice the service live of conventional fluids...60K intervals.