landover

Active Member
Can I use GL5 in defender transmissions - diffs, xfer box. gearbox ?

Please dont tell me I need 80/90 etc, this isnt a question about viscosity
 
Opinions differ.
Personally I stick to GL4 to be on the safe side.
Some say GL5 is OK for T/F Box but not Diffs, some say it's OK for both, some say the opposite.
 
GL5 is knowhere as corrosive as it used to be i use it in everything with 0 problems. i've consulted our oil supplier about it before and he assured me its a thing of the past, GL5 is just the highest grade now. oil technology has moved on leaps and bounds
 
Use gl5 in tcase and diffs on my 2 discos with no problems for a couple of years now. Not for use in the gearbox though, I use DII or The Morris lodexol stuff for r380s.
 
As far as I can gather, GL5 can corrode copper/brass/bronze etc parts. So perhaps I should be asking - which major components contain these ?
 
As far as I can gather, GL5 can corrode copper/brass/bronze etc parts. So perhaps I should be asking - which major components contain these ?

Iirc it's only Series gearboxes that have phosphor bronze bushes where gl5 is an issue.
 
transfer boxes do as well, diffs dont , though as 200tdi ayre said ive not seen any damage with using gl5 in t/boxes or series boxes
 
transfer boxes do as well, diffs dont , though as 200tdi ayre said ive not seen any damage with using gl5 in t/boxes or series boxes

So for clarity is it just Series gearbox/transfer box or later transfer boxes as well?

Sounds like it may be a bit of a non issue anyway.
 
series g/boxes and series t/boxes and lt230 t/boxes use yellow metal components, i think it is mostly a non issue
 
Ive been running GL5 in my 90 trans for the last 4 years
The same with the series 2 but for over 5 years
Mate also does the same in ho 90 and 110.
Ran GL5 in just about every land rover Ive ever owned
Current disco is silly syn stuff but as the diffs only hold 0.65 and 1.1 litres its not bank breaking, mind you the tfer box oil is 25 quid a litre!
 

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