Gearbox oil change

[gti mad man]

mine came out fairly easy apart from the hex fouling the exhaust

[irishkeet]

Well finally got around to changing the oil today (Aidan thanks for the advice)
The old oil smelled bloody terrible
The drain plug was a very small christmas tree which Im happy about
Flushed the box with a pint of the new oil before filling, job done for 20k

irishkeet

[jockstrap]

Hi
I bought a T25 Hitop 1.7D almost a year ago. As part of preparing it for use this spring/summer/autumn I changed the gearbox oil. I used Gforce EP 80w90 Hypoid Gear Oil Mineral GL5 Spec CC GFJ 455 manufactured by Tetrosyl Ltd. This was done before I discoverd this site!!
Can someone please tell me if the gearbox oil I have used will be Ok till the next change (20k) or should I change it ASAP. I am worried about my (brass) parts.

Ta

Alan

[gti mad man]

im sure aidan will be along to tell you more but as its gl5 spec im sure it will be fine

[ermie571]

whatever you use GL4 is the thing, not all GL5 are backward compatabile

err maybe not.

Phone Aidan mate - he'll very quickly give you the advice you need.....

BUT>> for the sake of £20 to get the one he recommends.....

Em
x

[Aidan]

I can't say it will be ok, modern gl5 probably is according to the suppliers, but I see the odd box with dissolved synchros (that sounds worse than it is really) so for £20 I'd change it, it's worthwhile watching the state of the drain plug and will only improve lube and shift.

[fairwynds]

hmmm, this is a good thread, I know Ive changed mine, but I am gonna check what went into it (twas recommended by the garage, so fingers crossed)
Thank you to Aiden for the knowledge...

[cozmik]

Is it all the same process & advice for my '83 1.6n/a diesel?

cheers

Cozzy

[little.legs]

Changed mine before going round germany and god knows if it'd ever been done. Black, thin, smelly oil and a xmas tree of a couple centimetres on the drain plug - I assume i'll need a new box/refurb in the future

Changed better through the gears afterwards tho. Gonna do it again soon as a sorta flush to see if there's much more crap on the plug. It'll have only done a coupla thousand miles between changes, but much was on the autobahn and more recently around the lakes & my mates got loadsa gear oil at his yard he lets me use.
Cant understand why people dont change it - may treat it to some GL4 following this thread and a couple more flushes.

[CovKid]

Would change mine but it seeps from one side where drive shaft meets the box. I gather you can put a new gasket in here but WIKI on this didn't make it too clear. Perhaps if I got stuck in it might.

[fairwynds]

Have changed the gearbox oil in my DG 1900 today, to the 75w90 as recommended..... LOVELY and smooth now!


Not much on the magnetic drain plug either (about 17k since last change....)

Thank you aiden for the info....