32 replies to this topic

[simplyminis]

using my rally car today and hit a rut quite hard and ive blown the diff, can i just change the diff of have i got to change the box aswell

[govig]

Take the box apart and see what's damaged.

[Carlos W]

or take the diff out and see what's damaged! It's easier than taking the gearbox apart!

Why do you think you've blown the diff?

[simplyminis]

no drive, make a noise when you try, ive had a mini with a diff gone before.
just was to know if i can just change the diff without changing the box or should i just change the whole thing

[Carlos W]

speak to Guessworks, I would've thought you could change just the diff!

Has it got an LSD?

If not, could you have broken a drive shaft or something?

[simplyminis]

no just a standard diff

[Ivor Badger]

Did the steering go strange just before the breakage?

[Carlos W]

not my specialist subject, but I'd be checking drive shafts and CV joints before taking diffs apart!

[samsfern]

I'd look at the driveshafts first, make sure the splines are ok as well.

[simplyminis]

ill take a look when i get chance now, when i put the clutch in to get a gear it make hell of a noise. no oil loss tho

[Cooperman]

With any rally car, if you have a drive problem you do really need to take the engine out and take it off the gearbox. Then you can inspect everything properly. If the diff pin has sheared then there may well be debris gone through the gearbox. In fact, you also should check the oil pump and crankshaft bearings for damage.
A rally Mini does need a cross-pin diff if it's putting out any serious power on un-surfaced and/or bumpy roads.
Don't take any chances, strip & check.
I strip & check my engine & gearbox after every 6 or 7 rallies even if there is no obvious problem. Mini transmissions are the main cause of retirements from ralliues - I've done many over the years.

[simplyminis]

im not into rallying in a big way just do a odd few and take part in local autotests.
ill have a look at the drive shafts 1st but will remove the engine and most prob put a lsd in it

[Cooperman]

For what you do a cross-pin diff is probably better than an LSD. I've been rallying Minis for over 50 years and have never got the hang of driving at a competitive speed with an LSD. They are great for racing, but not for road/rally use. My old friend Russell Brookes did the RAC International Rally in a Mini with an LSD some years ago and he reckoned that having the LSD cost him at least 15 minutes overall.
As above check the CV joint splines before stripping everything down. When you said you had blown the diff I assumed you had already eliminated the CV joints as a cause of the loss of drive.

[simplyminis]

no the car just stopped and thats about it, i had a bit of a strop put it on the trailer and thats it so havent had a good look just my 1st thought was the diff

[simplyminis]

forgot to say i wasnt going fast when it happened