A buddy of mine has been upgrading his truck over the past year and recently had his tranny built. Parts include DTT triple disk tc,billet input,output shaft and servo,performance clutches and valvebody kit with a mag-tec pan and ATS flex plate
Truck has an edge juice hot ,mach 4 inj.,HTT62-12, intake and exhaust and fass 150

After only a hand full off boost launches at the track the tranny is a wreck!Began by slipping following a boost launch(only 18psi).Drove the truck home with no problems.Next morning goes to leave in it and has no reverse.It was engaging but would not pull.Then notices the truck is trying to pull in park and neutral.Later that day he is showing me how it is trying to pull in neutral and whammo!!! something gives loose.Trans fluid everywhere.After looking for the leak can see that the over-drive housing is busted on the driver side.

So,he takes it to the guy that built it and he digs in. All the clutch packs are shot,something about a parking pawl being broke and obviously the o.d. housing.He precedes to repair it.Installs a milder valve body with new clutches and o.d. housing.
Now heres the problem as of now.The tranny builder has no idea what caused this and my friend is scared to death to go to the track with it.The trans guy is a good friend and very knowledgable with stock set-ups but admits this is his first built 47re.My friend bought all these parts and took it to him and wants to be loyal to our friend as he made good on the repair.But there is obviously something lacking on this build and I think its knowledge of how to adjust all this aftermarket stuff. Any input is as to why this might have happened and advice on how to properly adjust this thing would be greatly appreciated.

 

I think there were two separate issues. A: The parking sprag coming lose and tearing up the tranny housing, can be caused by the C-clip on the end of the parking sprag rod being damaged.

The pulling in neutral looks like wrong clutch clearances to me, this will also burn up the clutches in a hurry and send debris through the tranny. It can also be caused by internal leaks that bleed pressure to the wrong clutches (VB mounting plate damaged or internal cracks in the tranny housing).
The pull in park was a dead giveaway to the parking sprag because if park is engaged correctly the tranny output shaft is locked. I think it happened like that: Parking brake trouble, part gets lodged somewhere and blocks output shaft in reverse. Going forward it gets dislocated and waits for the moment to cause damage.

Due to the rather extreme damage I would suggest contacting DTT so that they check the VB for damages.

HTH

AlpineRAM

Disclaimer- I am no transmission guru! Just built a few of them ..

 

Appreciate it AlpineRAM. Do you know if the the clearances on the clutches is different between stock and performance set-up.My friend that built the tranny has built many old hotrod trannys(tuybo350,400,torque flights etc)just never a 47re.He installed a valvebody shift kit supplied by suncoast.Should we just have bought a modified one from DTT or Suncoast?Does anyone know what type of line pressures we should be seeing? Is there an optimum psi range we should be looking for?
I guess I'm just asking is there anything "special" that needs to be done on a 47re build up.WE have all the right parts to make this a stout tranny it just needs to be adjusted right.

 

Wow... what a mess.....

Ok... Forget talking to DTT. DTT will be well within their right to refuse to look or even talk about the trans now that its been opened and rebuilt by another builder.

I'm not sure what caused the failure. But thats not the issue anymore, since its rebuilt.

So we're down to the trans as built. You only say its a "milder VB". I'm not sure what that means, so I can't address that. As to adjusting the performance stuff, there are only three adjustments to make after the trans is built. The stuff that gets adjusted during the build shouldn't be an issue assuming the builder is as good as you say.

1) Rear band adjustment. It should be adjusted to the factory spec, unless its apply servo was modified by the shift kit. If so, follow the shift kit instructions.

2) Line pressure adjustment. The shift kit/VB modifier will have a spec for this, follow that.

3) Front band adjustment. This will depend on what apply lever is installed. If its a factory lever, follow factory spec.

Now, the question is, can the trans handle the truck on a drag run. That depends on the HP he is making at launch, and the mods to the trans. I don't know either bit of info, so I'll hazard a guess. If he's making over 300 hp, the mild VB probably isn't helping the trans enough to survive a full drag run.

More details would help.

 

There was a misunderstanding from my side here- I thought that the VB was built by DTT.

The clutch clearances depend on the pressures and low rates of the VB and the piston and the friction material used. So mixing stuff from different vendors is quite difficult. For the band adjustments you need to know the servo type and the apply lever ratio and adjust the VB accordingly.

There is no patent recipe for a performance tranny built with mixed parts.
If you get the shift timing wrong (and you will if you use a VB setup for stock components with performance servos, pistons, levers etc) you can get overlap shifting which will burn up the clutches and bands.

I'd start with rebuilding the tranny after a very thorough check for cracks in the housing and the VB, also checking the flatness of the VB mounting surface on both sides. If the VB is warped throw it away- do not try to mill it to specs unless you re-bore all valve bores. (shuttle valves that bind in warped bores are bad juju)

The precise specs for a complete system from any vendor are really specific to his setup, and they change over time because the vendors do improve their setups by changing parts. I'd suggest getting all the parts from one vendor and also get their recommended settings for this kit.
What a lot of gasser tranny builders do overlook on the 47's in a diesel is the importance of getting it leak free. The shaft bearing oil clearance does also play it's role in making the clutches last, because the amount of oil delivered per pump revolution is fixed, and the diesel with it's low end torque will load the clutches when there isn't much oil flow present.

HTH

AlpineRAM