Ba Typhoon Diff Issue

[turbocorty]

Hi Guy's

The other day whilst towing, I backed off the accelerator and I hear a very loud BANG from the rear end. This BANG repeated every time I backed off the gas.

I first thought it was a drive shaft or something, but after putting the car on a hoist, we found that the big bolt that stops the diff twisting had snapped.

The issue I have is...

About 2 year ago the rear end of the car was pulled apart for other work to be carried out and according to Ford's record's, the suspect bolt was replaced. The problem is that I purchased the exact same bolt (Same P/N) and it is at least 40mm longer than the bolt that snapped in the vehicle.

Q. Has anyone else had issues with this Bolt?

Q. Does anyone know why there are diffrerent size bolts? The new one I purchased will not fit yet it is the correct part number??

This would not be such a issue if it happened 3 weeks ago when it was still under warranty!!

Anyway, any help or advice would be great.

Cheers

[ORSMF6]

I have broken a few bolts over the three years ..

Just dont slam it into the next gear and go easy on the drive line and it will save it ...

[bcl]

1. yes, I'm familiar with that loud bang

2. the design issue with the original bolt is that it wasn't long enough

From : Has Anyone Broken A Diff Cover, A better diff cover

http://www.fordxr6turbo.com/forum/index.php?showtopic=31981

I had a problem with this 2 weeks ago.

I got some drivleine shunt, then the bolt that goes into the diff cover that holds the diff to the cradle snapped.

A new diff cover and longer bolt replaced it for now, but a better solution is required.

A few pictures:

1. The cradle, marked where the diff bolt will be inserted.

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2. The rear diff housing, with the snapped diff bolt stuck inside the housing.

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Brian

[t6xr]

Interesting!!!,mine makes similar noises when giving it a bit occasionally and

sometimes when backing off.I wonder if its the same thing? :holiday:

[iTec]

been there done that,

and yes brian I have broken my diff cover, funilly enough it was not replaced but rather "re-engineered" aka welded back up and that was at about 250rwkw

T6xr the sound you are probably refering to is driveline shunt, a londish thunking noise, if you have a damaged or worn out diff bush it will sound more like somebody tapping under the rear of the car with a hammer, mainly on gear changes or when going from on throttle to coasting and back again... the two are similar sounds, just the damaged bush makes it progresively louder as it gets more and more warn out. till you are left with a rather loud and rather annoying clunk clunk clunk pretty much all the time

the sound turbocorty is reffering to when he says he broke the bolt is more along the lines of somebody smacking under the car with a slegehammer when you have done it you will know you have done it!

[turbocorty]

OK....Finally ive got the car back together...

The long bolt was for all vehicles fitted with a big damper on the end of the bolt.

FPV does not use the damper on any of the vehicles - Possibly because the longer bolt breaks more easily?!?

Anyway, Replaced the bush, bolt and diff housing...How happy am I after ripping out the whole arsse end of the vehicle for one under engineered $12.00 bolt!!

The shorter bolt has the same P/N but ends in a "C" sufix.

Lets see how long this one lasts!!

Cheers

[t6xr]

Thanks iTec for the info. Getting it checked out next week.