It has been discussed here again but on older posts so I was wondering if there is any update or a clear answere since I have reed lot of different and opposite answers on this matter. I am currently using liqui moly GL-3 Is it safe to use on my 126 GB?

gordinir8 said:

It has been discussed here again but on older posts so I was wondering if there is any update or a clear answere since I have reed lot of different and opposite answers on this matter. I am currently using liqui moly GL-3 Is it safe to use on my 126 GB?

Click to expand...

It sounds like you have the right oil. I've talked some rubbish about this (and many other things) but finally hit on the exactly the right oil (if you're going by the original specifications) with this one from a seller who knows his Fiat 126 and 500's.

https://www.ebay.co.uk/itm/FIAT-126...e=STRK:MEBIDX:IT&_trksid=p2057872.m2749.l2649

Hi Fiat500, I am new to the classic Fiat scene having recently bought a 1967 500F. It has in its life time had an upgrade to the engine and gearbox presumably a 650 and gearbox from a 126. Am I correct in assuming that GL-3 will be correct for my car even if it turns out that the gearbox is the original box from a 500.

If the gearbox doesn't need to be double-de-clutched for 'down' shifts, than it will be a 126 gear-box. If you have a '650' engine in your car there is a very good chance that it will be a 126 gearbox. You can check which engine you have in the car by looking at the engine number. This is stamped into a 'flat' on the rear of the engine just to the right of the fuel pump.
I have a 126 engine and gearbox in my 500, and after consulting with "Castrol Classic Oils" I have put their 20/50 engine oil in my gear-box and suffered no problems. However, if you can get hold of "Liqui-moly GL03" as per Fiat's recommendation, then put that into it.

Thanks for the information, I definitely have a 650, confirmed by the “650” stamped next to the number 1 plug and the engine number. Have pulled both out so will see if I can find any supporting marks on the gearbox. I am reasonably sure it will be a synchro box the only slight doubt I have is shifting down to 1st can sometimes crunch so that may be me not pressing the clutch enough or is first not synchro like the old MG Midget boxes.

Golden rule with ALL the 500 gearboxes, irrelevant of type---do NOT change into 1st unless the vehicle is stationary. Often when I am sitting at lights etc, I will slide the gear-lever into 2nd, and THEN into 1st---it helps line every thing up in the gearbox.
Having '650' on the cylinder head is no guarantee that you have a '650' engine---check the engine number. There is very little difference externally between the 500 and 126 gearboxes. The main difference is the position of the starter---on a 500,the starter is at the top of the bell-housing,on a '126'gearbox the starter is on the side of the bell-housing (right hand side looking from the rear of the car)

Fiona500f said:

Thanks for the information, I definitely have a 650, confirmed by the “650” stamped next to the number 1 plug and the engine number. Have pulled both out so will see if I can find any supporting marks on the gearbox. I am reasonably sure it will be a synchro box the only slight doubt I have is shifting down to 1st can sometimes crunch so that may be me not pressing the clutch enough or is first not synchro like the old MG Midget boxes.

Click to expand...

I have a sync gearbox in my 500. There is no sync on 1st gear, only 2, 3 and 4th. Pretty stanrdard.

R

Small update here, i switched from liqui moly 75-W80 GL3 to 85-W90 GL4 as per liqui moly instructions concerning the 126 gearbox (i have 126 gearbox on) I can tell that gear shifting is smoother than before. I am changing gearbox oil every a year and a half since it coming out like black/silver color. My 3rd replacement was much better than the previous two with no metal particles in the magnetic plug and i think it runs a little smoother specially in 1st gear.