Thread: Gearbox went bang!

It has been on mine, not sure about Summiitt's.

Yep, front diff recall has been done...
2 days, bugger. As expensive as it is, you've just got to laugh...well try to at least!

All you can do is laugh - it is the only thing that got me through our ordeal - quite a nightmare, but when you look back on it all, it is quite funny - you couldn't write a script like what happened to ours and think that anyone would believe it - just a comedy of errors on all parts from the get go. Once it is repaired, and you are driving it again, the bad times soon fade because they are such a great car to drive.

Finally got the rangie back today, brand new transfer case, fully reco gearbox and everything that goes with it, including a big invoice!
Thoughts are that the failure was due to an abused gearbox/ driving style due to the twisted mainshaft, apparently almost unheard of in those GM boxes, bit scary considering the car only has 100,000km on it.All oils had been changed and the gearbox had some service history.

I haven't heard of the main shaft going on these boxes, but the output shaft twisting has been mentioned a lot in British forums and US Caddy, BMW forums. JPAT in the UK make a H/D replacement item:

http://www.jpat.co.uk/5L40E%20Shafts.pdf

Could this have failed ? and with the demolition of the transfer case the torque and pressure exerted back into the box twisted the main shaft ?

As a side note when they uprated this box to the 5L50E version they changed the number of teeth on the rear annulus gear, though post 03' boxes had the larger planetary gears and extra clutch plates found in the 5L50E. GM,LR and BMW knew they had a problem with this auto instead of a expensive recall they decided to do incremental updates by stealth and hope most would reach the end of their warranty.

For sure, initial loss of drive was due to stripped splines on the output shaft, then lots of damage to follow, as for the transfer box, they are almost a throw away as parts are hard to source, so a brand new out of the box one was installed. Thanks for the other info.

I guess you didn't pay $120 for a second hand transfer case at the wreckers then like I did :P I think I might stick with my Classic

Originally Posted by milld

I guess you didn't pay $120 for a second hand transfer case at the wreckers then like I did :P I think I might stick with my Classic

Yeah... The NV225 Transfer box in the L322 is a fairly complex bit of kit. I believe a new one would run to about $4K I think - not 100% sure. Summiitt would know, but that's up to Summiitt if he wants to share that with us.