Another auto trans question
Hotshot
Joined: Jun 2007
Posts: 10,008
Likes: 7
From: Austin, TX
Hey Darin, so I am just trying to understand...for personal reasons. I think my JW has taken a crap and I think it's the converter. I have never understood 100% how they work. If I stand on the brake and give it throttle, it should not rev to 3000, right? Mine did and then the tires kinda cut loose. I only did it for 3-4 seconds. It shifts great and all that, but it slips if it gets above 170* and then it won't go over 55mph without slipping. It throws the P1720 code (trans slip fault). Acts just like a TC unlocked. It's one reason I thought about putting a lockout switch on it.
I haven't wanted to put this on the forum, but I can't get JW to give me a call back when he can look at it and do the first fluid change. I need an answer because I can drive it, but can't tow with it now.
I haven't wanted to put this on the forum, but I can't get JW to give me a call back when he can look at it and do the first fluid change. I need an answer because I can drive it, but can't tow with it now.
Hotshot
Joined: Mar 2012
Posts: 10,590
Likes: 382
From: Texas
I guess I am wondering what stall should feel like. I'll test it again this morning. Should it feel like its going to literally stall the engine? I know, dumb question, but not sure. It will go to 2500 no problem when I am on the brakes and giving it throttle.
Hotshot
Joined: Jun 2007
Posts: 10,008
Likes: 7
From: Austin, TX
In drive and on the brakes. Slowly bring power in. You'll feel the converter grab harder and harder as RPMs rise and eventually RPMs won't rise any further, the truck may try to roll forward, or the truck will try to spin the tires. If you can't keep the truck from rolling through the brakes, you can't figure out the true stall speed of the converter. If that happens the best you can do is floor the truck from a stop and from idle and see how high the RPMs get. If you can get the truck to not push through the brakes or spin the tires until the engine can't raise RPMs any further though, that's your stall speed.
Hotshot
Joined: Mar 2012
Posts: 10,590
Likes: 382
From: Texas
In drive and on the brakes. Slowly bring power in. You'll feel the converter grab harder and harder as RPMs rise and eventually RPMs won't rise any further, the truck may try to roll forward, or the truck will try to spin the tires. If you can't keep the truck from rolling through the brakes, you can't figure out the true stall speed of the converter. If that happens the best you can do is floor the truck from a stop and from idle and see how high the RPMs get. If you can get the truck to not push through the brakes or spin the tires until the engine can't raise RPMs any further though, that's your stall speed.
Hotshot
Joined: Jun 2007
Posts: 10,008
Likes: 7
From: Austin, TX
Ok, cool. This is what I thought but wanted to make sure I wasn't missing something. This is what I did a few days ago. It went to 3k rpm before pushing and the tires chirping. I'll do it again this morning when I head to work and see what I get. I am pretty sure it is toast. I can feel and hear it lock in under normal driving, but any load on it and it slips.
Hotshot
Joined: Mar 2012
Posts: 10,590
Likes: 382
From: Texas
Yep, my thoughts too. Well f***...I haven't been able to get JW to answer my texts on getting it into him. I don't think he wants to fix it a second time. We'll see. I may just eat it and take it to a good shop here locally and get a new TC put it. I think the rest of the trans is probably fine. It shifts well and operates normally otherwise. The first time it had this problem, his help had overfilled it with fluid and it burned the TC up. I am beginning to wonder if his TC guy put out some questionable TCs last year.
Fleet Owner
Joined: Aug 2004
Posts: 20,419
Likes: 197
From: AZ
I even tried the front door approach and he wasn't there! Wasted several hundred miles of driving. He does what he wants, when he wants, why he wants and to he!! with everybody else. Mine is guaranteed for three years parts and labor and life time labor. That's why I don't get down on him but of course he might be reading this and just voided my warranty.
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Hotshot
Joined: Mar 2012
Posts: 10,590
Likes: 382
From: Texas
Originally Posted by 427 fordman
Byron, I think you have converter issues also, but I wouldnt' let JW off the hook. I'd be at his front door. It's under warranty, right?
Originally Posted by oldbird1965
I even tried the front door approach and he wasn't there! Wasted several hundred miles of driving. He does what he wants, when he wants, why he wants and to he!! with everybody else. Mine is guaranteed for three years parts and labor and life time labor. That's why I don't get down on him but of course he might be reading this and just voided my warranty.
Hotshot
Joined: Mar 2012
Posts: 10,590
Likes: 382
From: Texas
Originally Posted by z31freakify
Im surprise as I alwys read so many good eeviews from JW. Any chance your truck has an electrical problem causing the tc no to lock up (aka pcm)
Frmr Ford Trans Engr
Joined: Aug 1999
Posts: 24,738
Likes: 2,667
From: SE Florida
There are many things that could do that. None of them would cause the stall speed to go up to 3000 RPM. Put a switch on the system to force a lock, or put an LED in the circuit to see if the PCM is commanding the lock.