Now I'm Nervous....

I was going through some old service receipts from the previous owner of my XJ and found one from a 'quicky' lube shop. The previous owner had the tranny fluid replace with a GL-5 fluid, as well as the rear diff replaced with the same GL-5.

Now i know that the GL-5 is bad news in the tranny and it will be coming out this weekend. How much damage could have been done? It has been in there for about 8000 KM.

Is it bad to have the GL-5 in the rear diff?? It doesnt sound right to me.

Spec: 95, 5spd, 135000KM

THX

No its OK in the rear diff. Its the brass sychros in the trans that get eaten by the sulfer in GL-5

What the hell is GL-5? Is that some additive?

It's a type of gear oil

1985xjlaredo said:

What the hell is GL-5? Is that some additive?

Click to expand...

"GL" ratings are to gear oil what "S/C" ratings are to engine oil; except that, unlike the API "S" and "C" ratings, the "GL" ratings are not reverse-compatible. GL-4 and GL-5 do not always serve in the same places as GL-3.

The Aisin manual transmissions we deal with (AX-4, AX-5, and AX-15) all use bronze synchroniser rings for the forward gear ranges. GL-5 gear oil has added sulphur as an EP (Extreme Pressure) additive, and that sulphur is antagonistic to copper alloys (like bronze.)

Extended use of GL-5 in an AX-series box will eventually result in synchroniser wear - which will accelerate gear wear. Those of you who have driven transmissions without synchronisers know what I'm talking about - the synchro rings help to "match speeds" with the gears before you shift, so you don't gnash the gears trying to shift. Double-clutching is probably something you should learn anyhow...

GL-4 may, in most cases, be used in place of GL-3. I think there is a slight amount of added sulphur in GL-4, but not so much to cause a problem. However, if you have an Aisin gearbox, the use of GL-3 is preferred.

Note that, if you have a 2001XJ w/4.0 and five-speed, you have an NV3550 - and that has its own synthetic gear lube. I haven't sorted out a possible replacement for that yet...