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MG MGF Technical - gearbox oil

Hi all,
An other question for you,
Do you know when we need to change the oil in the gearbox,
and what change to have new oil in the gearbox.
My car has 80.000kms now and i need to bring it to the garage
cause i had a HGF, :(,
so do you thing i need to change it because sometimes the first gear is pretty hard to enter or maybe it's because the temperature outside is really cold, is it the same for you ?
Thanks again for the reply and have a good day.

My understanding is that originally the gearbox was specified as 'filled for life'. However, the service sheet for my ZS180 (which also uses the PG1 gearbox) states oil change at 150k miles (if memory serves me correctly).

There was (is?) a problem where the gearboxes were only partially filled at the factory. This might be your problem.


For the cost of a drain and refill, I have found that the gearbox operates with more precision and is generally smoother. I echo the point made by Ralph, that the box is sometimes not completely full.

Tony H

Mine was certainly better and quieter after a re-fill.
Steve Ratledge


I just filled up missing oil in last year.
Castrol SMX-S
SAE75-W-85 API GL 3/4
Pleased with it so far. Gearing got much better.

Anyway, In the meantime I heard, it should be better to change complete to the _selected_ oil, instead of filling up ?

It's said to be not the very best idea to mix Castrol SMX-S with the existing original MTF-94.

?? ideas ??

PS. ;-)
Dieter K.

dieter after reading this i think i need to check mine as i have a new job that takes me up and down the motor way i think i will drain and refill mine just to be sure do you reccommend castrol smx-s or anything different

Hi all,

I will need to change my gearbox oil soon.
What oil do us "downunder"'s use? Brand and Type?


no recommendation, I just looked up parameters myself after a discussion in this BBS years ago.
Went for a shopping tour through several car parts shops in DE until I found that most compareable and *doesn't hurt*

There might be better ??

---- original MTF-94 ----
Rover Group
MTF-94; R380, PG1 & H gearbox approvals
Honda MTF-7289
MG PG1 gearbox approval

SAE Viscosity 75W-80
Density at 15C, kg/L 0.870
Flash Point, COC, C 185
FZG, Load Stage 11
Pour Point, C -45
Viscosity at -40C, cP 60,000
Viscosity at 40C, cSt 53.2
Viscosity at 100C, cSt 10.50
Viscosity Index 190
Full Synthetic 75W80 GL-4
------------- said the data sheet ---


SAE75-W-85 API GL 3/4
_is_ the grade of the SMX-S

So I poored that in.
Dieter K.

Add on 4Branko ;)


"CALTEX ... any more questions?"

PS. No worries, The _spy_ (professional purchase) is said to find everything ... nearly :)
Dieter K.

Hey, thanks Dieter, you're a legend.!

You sure you don't live DownUnder?


I have just had mine filled up as it had literally none in it.... the car has only done 45k needless to say it was much, much better after it actually had some oil in it, lol
Nick Lewis

I checked the service schedule for my ZS last night. The gearbox oil change is at 105k, not 150k as previously stated. My F did 158k without a gearbox oil change!


This thread was discussed between 07/03/2005 and 09/03/2005

MG MGF Technical index

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