MattSapp95_T/A

iTrader: (35)

I just put together a car for a friend and we installed a Rebuilt TH400 with a trans brake...it has a brand new circle D converter, SFI plate, super Cooler etc..


We put a deep pan on it and verified the clutches were new.. Put it in the car and took it for a spin.. If you put it in first and take off easy or even a little power it drives fine... if you try and get on it hard in first it will pull for a second then as it gets up higher it basically just free revs and dosent pull... soon as i shift into second it pulls fine and so does 3rd...

it is a reverse manual valve body...

I have pulled the trans brake solenoid out and made sure it wasn't sticking, verified the shifter cable was adjusted properly and also made sure the trans was full.

can anyone shed some light on this.... as for cruising around the trans feels fine as long as I don't get on it in first at all....


Thanks

thedudeZ

iTrader: (14)

When you put the deep pan on did you verify the pickup tube/filter depth was down to the bottom of the new deep pan?

Also on the portion of the pickup tube that goes into the bottom of the trans case did you make sure you had 2 orings on the tube.

Sounds like a fluid pickup issue.

93camaro_zzz

iTrader: (13)

Thats a good place to start thedudeZ. Also, if you happen to need a filter extension, I have one at the house I do not need. It is a brand new B&M one for TH400, just don't need it is all. Pm me if you want it.

MattSapp95_T/A

iTrader: (35)

Thanks Guys I did put the extension on it however I don't know if it had 2 orings or any for that matter. WOuld that cause the issuewe are having? wouldn't it do the same thing in all gears? Also someone told me maybe the pump seal got cut??? Thoughts??

I am going to check it today...

thedudeZ

iTrader: (14)

If it didn't have any O-rings on it you will have issues for sure. It won't be consistent at any rpm or gear. Get the pan off it and check. I believe from GM they came with 1 o-ring and the service bulletin called for 2 O-rings I believe? Also the filter should be able to pivot back and forth so make sure it isn't tightened down solid to the valvebody.

MattSapp95_T/A

iTrader: (35)

Pulled it apart and it had 2 orings in it...

we pulled it back out and I pulled everything apart... It is suppose to have a TCI trans brake but the valve body has a GM part number? Does TCI just modify GM bodies? Also there are NO gaskets between the body and seperator plate or the plate and the trans? is that right?

Pulled the clutches and they all look good except the direct drum.. All the steels are warped and look like they have gotten really hot... Also it is a 4l80 drum but it only has 8 springs on it and everything I have seen for trans bakes call for 16 heavy Duty springs?

there is also a lot of clearance too... def more the .10 per clutch...

Thanks for any help

72blownvert

Most transbrake valvebodys are made out of the oe castings. It is normal not to have valvebody gaskets.
Putting only 8 springs in the drum is just plain dumb,you are correct that you need all 16 heavy springs. Look to make shure theres a bleed hole in the direct drum. The clearence should be set at 60th overall clearence.

MattSapp95_T/A

iTrader: (35)

Thanks blownvert! What will happen if they only put 8 springs in the direct drum?

Also what is the benefit of running no valve body gaskets?

72blownvert

The theory behind less springs is that that the clutches will apply faster which is not correct. The springs are there to release the clutch pack. With only 8 springs there is not enough pressure to get the clutch pack released and the clutches drag and burn up quick especially on a t/brake unit. The reason you need real stiff springs w/a transbrake is that the stiff springs help in the quickness of release of the brake along with clearence of the clutch pack,also to help with the clutches trying to apply at high rpm which is why you also need a 60th bleed hole in the drum.

There is really no benefit using gaskets, when using a brake valve body you need to make sure the case is perfectly flat to prevent cross leaks so there is no need for gaskets. If you are worried about flat sanding the case TCI does sell gaskets for there valvebodys.