Gearbox fluid

[CMF_BOX]

I was reading in the articles section that VMX80 is best used in the micra gearbox. is anyone using anything different?

I got 3L of castrol EPX 80W-90 that has been sitting around for a few years that I was considering using in the micra. Anyone think its a bad idea?

 

[CMF_Mike R]

check out the EPX bit first , I think it stands for Extreme and involves the use of additives that can attack certain metals in a gearbox , it was not recommended for use in a Fiat I had for that reason .

for example :-
http://www.fiatforum.com/x1-9/182923-gear-oil.html

 

[CMF_Micra_King]

I used Castrol VMX80 when I did my gearbox and its crap oil. I think others have said the same. https://micra.org.uk/cmf/message/23223
I keep meaning to change it to something better and hear royal purple make some good gear box oils which I plan to use.

 

[CMF_BOX]

Might just have to get some more VMX80. dont really plan on doing anything special with my micra to put the good stuff in it.

 

[CMF_Rudy]

hmmm, I just filled my box wiv vmx80

 

[CMF_1300cc]

i usually start my engine at 630 in the morning and shifting is not smooth for the first 5 minutes, what fluid should i be using....will oil additives needed......

 

[CMF_Mike R]

interestedly it may be worth putting a bit of oil on the ball pivot at the bottom of the gear stick ... just lift the gaiter and put a drop on .. it made a lot of difference to my shift .

 

[CMF_1300cc]

K, illgive that a try, but i thought it will b the gearbox itself is the priblem coz its only happen inthe morning when its really cold

 

[CMF_mycra]

Castrol VMX80, Castrol Syntrax, Valvoline 80-90...same **** generally these SAE acheives viscosity through high use of additives. which breaks down, unlike double easter or full syn. resulting in a reduction in its kinematic viscosity, thus harder to shift, poor syncro performance and loss of protection from high heat(gb is air cooled if makes any difference at all).

if you're using for daily perfect
if track use sae 90->140+ full syn

 

[CMF_1300cc]

Hey mycra, hav u heard of promax oil additives

 

[CMF_mycra]

they are a American company from memory...they do alot, from water/fuel pump to timing belts... their mechanical parts are mostly Japanese or chinese(US iso spec). oil lube is basic commercial quality from what i heard, nothing special. not many people carry them on the shelf...distributor is ATAP

 

[CMF_Bishop]

I read interesting some stuff recently looking for answers myself, apparently VMX80 is just not that great, it's been sited on some other sites for giving a poor shift quality, which is weird when you read it's supposed to improve shifting feel.

Overall I found if you want something with real cold shift ability, while retaining a real 90W hot shift protection, you 'need' a synthetic or semi synthetic gear oil, which means a 75W90 oil, and not a 80W90 or straight 90W which will usually be non synth oils.

I was going to use Penrite 75W90, but could not find any, in the end I bought some Nulon, which while I'd not normally touch their stuff, I hear their base oil products are ok now, though I have yet to actually do my gear oil so can't say for sure yet if it is any good.

If you check Bob Is The Oil Guy or other, 80W90 etc is car makers cheap-ing out on spec oil, saving $ on the factory fill...

 

[CMF_mycra]

1300cc not many addictive available... and good ones waste if you're running crap oil. but first do check ur gb oil levels, bushings and clutch cable.

some companies have a PTF based solution which sticks and changes metallurgy surfaces for better performance and protection. from memory Slick 50 has a decent one but it's around $40-50 mark.

 

[CMF_frank2]

a couple of msc members have posted that their gears were notchy when cold after changing oil (probably just more viscous and slowing the syncro,s down imo)
and millions of austin rover cars used the g/box as an engine sump and hence used dirty 20/50 as its gearoil eh (with no ill effect)