The restoration of #436

[E_T_V]

Hi again everyone, a follow up question from me ....

Is the MTF94 (the "genuine rover gearbox oil") the one to use in the 5 speed Montego 1991 vintage gearbox?

At the back of my mind I seem to have read the 5 speeder was a Honda manufactured gearbox. So should THAT one have the 10/40 engine oil not the MTF94...

Thanks again in advance folks!
John

The short version is the PG1 (the Honda box) should use MTF94.

The longer version is:
Originally Austin-Rover recommended 10w40 for the cars and SAE90 for the vans both changed at regular intervals.

Then along came the rover 200/400 using the same box and in the turbo it was recommended to use 75W80. There were lots of warranty claims for dead gearboxes.
They then standardised the oil to almost all boxes used in the MG-Rover range at that time to MTF94 and drastically increased the service interval. This helped marginally with the warranty claims on the turbo versions and also decreased the number of oils that needed to be stocked so saved cost. The MTF94 was essentially filled for life, but I think some service plans had a first change at 100,000 miles.
This is the oil that was used in all subsequent PG1's and so is what I'd recommend to use.

10w40 will work fine in all but the torsen differential equipped gearboxes, but will need changing regularly. Any oil in the gearbox is better than low oil level which will quickly wear out the differential bearings.

The original PG1 gearbox on my 600 ran to well in excess of 250k miles before the differential bearings finally wore out, and that has more torque than all but the most modded of maestro/montegos so MTF94 seems to work well in my experience.

[Sussex Pete]

Looking well as is Pete - I see it has early montego turbo intercooler pipes. Will you be returning the wheels back to standard cross spokes? I have full sets of 5.5J and 6.0J if your looking? Another one getting restored - good stuff!

Thanks Mike! Thats what I thought as well, but looking well is only from a distance, once you get up close you see the level of tinworm infestation and poor body repairs from days of yore
When you mention montego intercooler pipes - are these the flexibles or the alloy tubes. Whichever I'm think about using silicone to replace most of the pipe runs. As for wheels, I really have thought about what to do there. When the time comes to roll it out into the daylight once more I will revisit this quandary.

[Jeff Turbo]

When you mention montego intercooler pipes - are these the flexibles or the alloy tubes. Whichever I'm think about using silicone to replace most of the pipe runs. :

The 2 pipes that run from the intercooler to the carb and turbo etc. The ones on your car are from an early MG Montego Turbo.
You can get modern Samco boost pipes but for the later models, you would need to change the metal pipes etc to make it look more original.
Depends on what your doing to the car, going back to original or not?
When you have stripped the seat covers let me know as it will remind me of the companies phone number etc as it escapes me at the moment, yet another senior moment

[Sussex Pete]

The 2 pipes that run from the intercooler to the carb and turbo etc. The ones on your car are from an early MG Montego Turbo.
You can get modern Samco boost pipes but for the later models, you would need to change the metal pipes etc to make it look more original.
Depends on what your doing to the car, going back to original or not?
When you have stripped the seat covers let me know as it will remind me of the companies phone number etc as it escapes me at the moment, yet another senior moment

The way I am thinking at the moment is to try and keep it as original as possible but allowing for the use of modern materials where appropriate. Changing the metal pipes is something that is already marked as possibly needed as the middle joint between the pipes has split and I'm not sure if it is (neatly) repairable.

[grout20]

Thanks...

The short version is the PG1 (the Honda box) should use MTF94.

......

The original PG1 gearbox on my 600 ran to well in excess of 250k miles before the differential bearings finally wore out, and that has more torque than all but the most modded of maestro/montegos so MTF94 seems to work well in my experience.

Hi E_T_V

Great response to my question.... MANY thanks .... MTF94 for me, then!


cheers
John