48Re Nightmare

Tincup

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Anyone have experience with the 48RE in our trucks?

I was having a problem with the converter not un-locking and it was stalling the engine. After doing a ton of research on line, I tried a few different things ( band adjustment, different fluid, even a new stock converter) this made it better, but it would still do it once in a while.

Fast foward to last December, I found a young guy on line (Loganbuilt transmissions) who agreed to rebuild it to 800hp capable, new billet input shaft, new valve body, tripple disc converter, etc. So I yanked it out and shipped it to Kentucky.

I got it back in January, reinstalled it, but didn't get a chance to drive it until the weather broke in May.

I filled it up with 15qts (plus 1 in the cooling circuit) and took it for a ride, everything seemed fine, shifter good, no issues, till I got home and left a trail of fluid
up my driveway. I contacted the kid and he said that I over filled it and it was coming out the breather/overflow vent ( it was leaking from behind the converter) So I removed 1 qt.

Kept driving it seamed ok, but would still get a few drops everytime I drove it ( never really far)

First of June I drove it to work (17mi) got to work and left a trail into the parking lot, the underside of the truck was covered with fluid. Now I'm panicking!

Contacted the builder, who contacted the manufacturer of the parts (Goerend ) . I had several phone calls with both parties, (bothe were very helpful) They had me check a number of things, but in the end, It still kept leaking ( or slipping if I removed any more fluid). The owner of Goerend had me pull it out and send it to Iowa so he could run it on his transmission dyno.

He ran it for probably 40 hours and "of course" it never leaked a drop.

So they have a trick they use on the race trucks where they relocate the vent to the rear of the trans, and block off the one behind the converter. I wasen't crazy about this, but what else can I do?

I am not 100% sure this will solve the problem, the trans is on it's way back this week ( I have lost the whole summer ).

MY question is, I am still running the stock flex plate, with the billet converter, is that an issue? ( I don't plan on racing it) should I use the billet flex plate ($600) ? would it make any difference?

Anyone have any thoughts on what else it could be, I hate to put it back together and have it still leak.

Thanks
 

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The two most likely leak areas are the front and rear seals as there aren't that many areas the fluid can be coming from.
If the fluid is coming from the convertor area, the front seal, or the front pump gasket.
In rare cases, the convertor itself can leak. I had a billet unit with a bad weld.

And no, a different flex-plate won't make any difference.
 
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The two most likely leak areas are the front and rear seals as there aren't that many areas the fluid can be coming from.
If the fluid is coming from the convertor area, the front seal, or the front pump gasket.
In rare cases, the convertor itself can leak. I had a billet unit with a bad weld.

And no, a different flex-plate won't make any difference.
Thanks Ronnie, The guy ran it "as is" and had no leaks, same seals and gaskets. I'm just nervious that it's still going to leak. Guess I won't know till I put it back in. Do you think 14qts of fluid is too much? if I put 13 it slips...
 
Anyone have experience with the 48RE in our trucks?

I was having a problem with the converter not un-locking and it was stalling the engine. After doing a ton of research on line, I tried a few different things ( band adjustment, different fluid, even a new stock converter) this made it better, but it would still do it once in a while.

Fast foward to last December, I found a young guy on line (Loganbuilt transmissions) who agreed to rebuild it to 800hp capable, new billet input shaft, new valve body, tripple disc converter, etc. So I yanked it out and shipped it to Kentucky.

I got it back in January, reinstalled it, but didn't get a chance to drive it until the weather broke in May.

I filled it up with 15qts (plus 1 in the cooling circuit) and took it for a ride, everything seemed fine, shifter good, no issues, till I got home and left a trail of fluid
up my driveway. I contacted the kid and he said that I over filled it and it was coming out the breather/overflow vent ( it was leaking from behind the converter) So I removed 1 qt.

Kept driving it seamed ok, but would still get a few drops everytime I drove it ( never really far)

First of June I drove it to work (17mi) got to work and left a trail into the parking lot, the underside of the truck was covered with fluid. Now I'm panicking!

Contacted the builder, who contacted the manufacturer of the parts (Goerend ) . I had several phone calls with both parties, (bothe were very helpful) They had me check a number of things, but in the end, It still kept leaking ( or slipping if I removed any more fluid). The owner of Goerend had me pull it out and send it to Iowa so he could run it on his transmission dyno.

He ran it for probably 40 hours and "of course" it never leaked a drop.

So they have a trick they use on the race trucks where they relocate the vent to the rear of the trans, and block off the one behind the converter. I wasen't crazy about this, but what else can I do?

I am not 100% sure this will solve the problem, the trans is on it's way back this week ( I have lost the whole summer ).

MY question is, I am still running the stock flex plate, with the billet converter, is that an issue? ( I don't plan on racing it) should I use the billet flex plate ($600) ? would it make any difference?

Anyone have any thoughts on what else it could be, I hate to put it back together and have it still leak.

Thanks
That a pertty looking Transmission .. The red makes it tough to see where leaks are coming from ..
My guess front seal or possible O-rings on sensors , gaskets maybe at the pump ...
seeing that they dynoed the trans and found no leaks does make me think the converter .
 

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