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lock up problem with suncoast

1145 Views 23 Replies 3 Participants Last post by  2000cumminstroke_this
I got a 97 12 valve 4 wheel drive with a freshly rebuilt 47re. Got a billet input and a suncoast triple disc converter. I have had lock up issues ever since I have had tranny rebuilt. We have had the tranny out 4 times trouble shooti g the problem. The converter will only lock if you let off the throttle or stand on it real hard,once in awhile it will lock on its own but not very often. We tried new valve body, lock up solenoid, pressure tested all lines and passages in tranny. Only thing that fixed the problem was putti g the stock converter back in. Sent converter to suncoast to have checked out and tbey said it was fine. Any ideas on what the problem could be?
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if putting a stock tc in fixed the issue then I would think that the suncoast tc is having issues. Seems logical.
So you are saying that you dont have any lock-up issues with the stock converter at all? Hrmm thats odd.. I was going to say try taking the fuse from the alternator out and see with that would fix it, but if its doing just fine with the stock converter i would say you are having some sort of bypass going on inside the converter from SC.
Well that's what I thought to but they said there is nothing wrong with the converter and that I probably got another issue
Lockup is just fine with stock converter. Locks up everytime like its supposed to.
Sounds like you diagnosed your own issue to me. I can't see how they would say that it isn't the issue since it works with a stock tc.

Only other thing that comes ot mind is you might not have enough line pressure for the triple. Not sure if that matters when using a triple compared to a single. Tv cable adjusted correct?

When you let off and it locks does it stay locked? IE: let off to lock the tc then go to %50 throttle. Does it unlock/slip or stay locked?
Then I would ask for my money back and call Frank at Revmax. Done and Done!
Not sure how they tested it but the tc guy at suncoast said everything looked ok and they put new seals in it, I told them the probs I was having and theh didn't charge me labor for the inspectuon which wouldve been 450 bucks. I have actually been doing some research on the revmax converters.
Never shuddered with either converter
From above:

When you let off and it locks does it stay locked? IE: let off to lock the tc then go to %50 throttle. Does it unlock/slip or stay locked?
yeah man...get your hard earned money back and a real converter...Built by a Damn good builder. I've been to their shop these guys dont B/S around son!
When it locks it stays locked. I got a lock up switch and has the same characteristics when I flip the switch. Either got to back out of it or get into it real hard for it to lock up.
i dont see how it could be anything other than the tc then.
That's what my tranny guy and I both thinl but they said its fine. Just wanted to get some other opinions on my situation. I spent a lot of money in parts and labor trying to get this problem fixed and I don't really want to put this converter back in and still have the same issue. Are them revmax converters tough, I sled pull and drag race my truck quite often
I like mine.

whatever that's worth
HAHA are they tough...I have pulled a few sleds and my 28 gooseneck with 75-100hp tractors on it all the time. They are tough if you ask me.

Just look at that sexy billet converter.
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Ive never seen a SC converter but the the billet cover on Revmax's converter is thick...well machined piece of steel that will handle alot of heat. Also the billet pressure plate on the inside of the converter that presses against the 3 disk is sexy too...I called a few buddies over to just sit around and drink beer and talk about how badass it looked before i put it in.
What do your trans temps usually run just out of curiosity
normal driving on the interstate running 65-70 around 140* Intown stop and go 180-200* pulling my trailer on the interstate is about 160*. and middle of summer i have seen 210-220* in stop and go. Ill have to look at the edge to see what the max has been but thats a normal day.

Now i have a Revmax low stall converter in my 91 flatbed dually 4x4 cummins and I see ave. temps of 200-240 in it without the lockup converter pulling the same trailer. but i can tell you this...that converter alone on a stock motor made a huge difference on that truck when it comes to pulling power. It will flat out pull.
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