type of oil in diff

[grasshopper]

Hi all. I think my diff may have GL 1 oil in it. Should it be gl4 ? Should i be worried if its wrong oil ?

[geospider]

since I was only 13 in 1976 when your car was built, I don;t know this for sure. But I bet GL1 was all there was when your/my (79) car was built, so it's fine. But, given there is now worry of degrading the yellow metals. as in the trans, you can put the others in, from what I have read on this forum. And I am sure they are of better lubricating value. I believe I used the Lucas 80/90. But I have quite a few oils in my cabinet.

there are a few on here who will/can be very technical on this.

geo

[Odoyle]

Differential needs gear oil with EP additive or you will need a new rear axle in no time. GL1=glitterbomb