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Discussion Starter #1 (Edited)
Okay, so I did my first tranny rebuild, now the sky is falling.

96 T-bird, 4.6L. Ran great before rebuild, minus the slipping trans.

Just finished putting the car back together tonight, and initially when I tried reverse, it would only randomly catch, and the more revs, the less it caught. After quite a few tries, I eventually could drive in reverse as long as I was below 1200 rpm and not going up a steep hill. At anything over 1200 RPM, it slips like there is no tomorrow.
Drive wasn't much better, but after a few tries, I was able to take it out on the road, but randomly I got some shudder, mostly when I step on the gas. By shudder, I mean almost like a "miss", or hitting some bumps in the road at high speed. Not a slip exactly, just like a misfire.
When I get it down the road, it shifts like a dream, which is a big improvement, although it seems to rev sort of high in 4th gear, almost like there is no overdrive. I was at 2K at 60mph.
So, shifting is way better than before, but I gotta figure out this reverse thing and the shudder. Also sometimes now when I put it in gear, the car will stall. It almost acts like it can't handle being in gear. Never did that before.
When I did the rebuild, I replaced all the clutch plates and steels as well as gaskets on the valve body. Also I used a rebuilt torque converter. I am sort of leaning toward
A. I got a bad torque converter or
B. maybe the shift linkage is slightly off. I know that seems like a long shot.

The tranny went back together VERY well, and everything seemed to fit back together like it should, so I am kind of lost. Unfortunately, I just bought this car, and I did not have the money for a pro trans job (would have been more than I paid for the car) and I have to figure this out and fix it ASAP as the wife starts a new job tomorrow, and I am relegated to driving the old pickup, and I miss my t-bird. Been out of commission during rebuild for 3 weeks. So any advice would be GREAT!!
 

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Wait until a Guru Checks in but IIRC last time I saw this it was major Low Pressure problem - I would park it until you get expert reply.
 

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did u replace the sprags?

did you check the epc solenoid to see if it had debris in it from the old trans failure?

hope u flushed the lines and radiator before you re-assembled her

as BUCK said, I'd wait for a more knowledgeable trans guru to chime in
 

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& When OP says "Shift Linkage may be off" I;m assuming OP has already triple-checked MLPS Alignment right_____?

IIRC in Reverse or Manual 1 you get "full pressure" so NOT getting that can often mean a key Seal was mis-assembled.
 

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Discussion Starter #5
What is MLPS alignment? I had a buddy who has done a couple rebuilds in his younger days supervising me. I am not 100% confident he was as expert as I originally hoped. The old trans had some severely worn intermediate clutches (the large ones behind the pump). Other than that all the clutches and steels were in pristene condition. I replaced them anyway though. I did not replace anything other than clutches/steels, and the pump gasket, valve body gaskets, plastic bearings in the valve body, and the torque converter(reman). I drove it again tonight, and it shudders REALLY bad when I get on the gas, but seems pretty smooth if I take it easy. Same in reverse as long as I keep the rpms down.
 

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Also, it may help to pinpoint the problem by reading gauges attached to the trans pressure test ports. Follow manufacture spec' for proper pressures. Not sure if these gauges are available at part store loan programs.

I'm thinking you may have to remove the trans again, and make another attempt. It sucks, but it's not all together uncommon. Don't feel bad. It happens to the best of us. As my auto mechanic instructor use to say, "If you've never made a mistake; you've never done nothing". (I write this for the most part because you stated this is your first trans rebuild.)

I'll add, should you in fact remove the trans, perform bench test with air of clutches for seal integrity, and servo activation for proper band application before installing valve body on case. Study clutch/band application chart in order to pay particular attention to those components that are applied in relation to the problem the trans is having.

You should hear a slight thump when the clutches engage, and no sound of excessive air passing by any lip seals. Same with servos piston activation, and redundant check of proper band apply/release function. Follow the book to know where to place the rubber tipped air gun, and lower the hose air pressure to about 30 lbs.
 

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Discussion Starter #7
Am I completely off base thinking I may have gotten a bum torque converter? Also what about the torque converter solonoid? Looking at all possibilities if I have to remove it again. I am pretty certain that is going to happen.
 

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Discussion Starter #8
Oh, and one more thing I found when I drove it again today. When I step on the gas when it's out of gear, the engine is rough coming up to speed. Wasn't like that before. It actually shakes a bit until it comes up in rpms. it was smooth power before pulling the tranny. Is this connected or new, I have no idea.
 

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Oh, and one more thing I found when I drove it again today. When I step on the gas when it's out of gear, the engine is rough coming up to speed. Wasn't like that before. It actually shakes a bit until it comes up in rpms. it was smooth power before pulling the tranny. Is this connected or new, I have no idea.
It's Déjà vu for me because I just put an 02 tranny in my car and had the same issues and was worried. 40 minutes and 8 new sparkplugs later it ran like a champ again.
 

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Trans shudder is usually caused by the torque converter clutch. I stator one way clutch not holding will cause poor acceleration performance. During a road test these symptoms are not the same as a trans that is slipping like there's no tomorrow. When slipping occurs, either by a clutch not applying properly, or a clutch drum not holding, the rpm's will runaway, and the car doesn't move in direct proportion.
 

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First thing we usually check for is proper fluid level. You sure its topped off after running it through the gears, etc ??
 

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Discussion Starter #12
Checked and double checked the fluid level. It runs through the gears fine. The only real slipping I get is reverse. Drive works and I don't get any rpm runaway that I can tell. Just the shudder. I will consider the spark plugs. Not sure why they would need changed after a trans rebuild, but I'm willing to try anything. In fact, I am considering just getting a remanufactured trans and pulling the plug on this one. Thoughts on that?
 

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If one doesn't have any experience overhauling automatic transmissions, and no formal training. A lack of proper tools, and equipment to perform a quality repair, then yes, I would recommend a trans remove and replace.

Only you yourself can set such limitations.

Cautiously optimistic I write, however, that if this is in fact own your car, and it's your money, your time, I think it would be an excellent opportunity to continue cutting your teeth on this repair.

Reverse narrows it down quite a bit.

Study the book. Make sure you have all the right tools, and perform all the checks, and bench tests. And I do mean...all. Even if one simple little thing is off the trans will not perform correctly.

As for the torque converter, a shudder is usually caused by old depleted friction modifiers in the fluid. Perhaps the torque converter clutch in the one you installed is worn fubar. Sure can't tell form here. Bench test the TCC solenoid.

Shudder/vibration can also be caused by worn bushings in the trans. Double check U-joints too.

Wish I was closer to come over and help you out.

The best advice I can give you is to study the book thoroughly, perform all checks, make changes when needed, and take your time to get it right.
 

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Discussion Starter #14
I have a book on the way, and have been researching the TCC solenoid. I cannot find anywhere to buy one though, if mine turns out to be bad. Can anyone set me on a website or location that will have one? I am VERY appreciative of all your help and advice. I, too, am cautiously optimistic that I can figure this out, and yes, I will continue cutting my teeth on it. It would be much more enjoyable if I had a lift, but I'll get it, one way or t'other. I am active duty Navy, so time has been limited as to when and how long I can work it. I'll continue to post as it develops.
 

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Did you have seal installers for the new seals?

Some of the seals are really hard to get in right without sizing tools.

Check this thread out:

http://www.explorerforum.com/forums/showthread.php?t=128800

This is the guide I'm currently using, lol.

Any one thing will make it not work; a thread off a red rag in a checkball cost me ~$200 once. :)
 

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The TCC solenoid should be available at the Ford dealership.

Any time I rebuild a transmission, the torque converter is replaced with a re-manufactured one. No way to tell how much debris got stuck inside and no way to get it out so just replace it. Same with the radiator / cooling lines, flush them out very well so you dont have a repeat failure shortly after a rebuild.

Seals are very important to get in just right with the proper tools, one little nick in the seal may work the first time and then after that it just wont engage. I always bench check all of the clutches by assembling the transmission internals with the pump outside of the casing and then use air to check clutch operation through the pump.

Right now since your transmission is already installed in the car, about the most you can do is put a pressure gauge on the tap outside of the transmission and check pressures while running it through the gears. Reverse is fully manual, so no electronics would affect its engagement.
 

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Discussion Starter #17
It turns out my book will not be here till next week and I have some help coming out tomorrow to pull the trans again and replace the torque converter, so can anyone post the bench test procedure for the TCC solenoid? I am going to give this another shot. Hopefully I can get this car back on the road by Saturday night. I miss it...
 

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Discussion Starter #18
Right now since your transmission is already installed in the car, about the most you can do is put a pressure gauge on the tap outside of the transmission and check pressures while running it through the gears. Reverse is fully manual, so no electronics would affect its engagement.
Where do I find this tap? I am not against going to buy a tool to check pressures if it will help me diagnose prior to pulling the trans out again. Also what pressure am I looking for in all the gears?

I know, lots of NEWB questions, but I don't have my book yet.
 

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Discussion Starter #19
I figured out the reverse I think. The accumulator snap ring wasn't set right so the piston was cocked. I got the tranny all back together now, but when I tightened the pump in I heard some popping from the inside of the case, so unless someone out there tells me that is to be expected, I am going to take it back apart tomorrow and inspect...
 

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Discussion Starter #20
Quick question. If I did not prime the Torque converter or pump when I put the tranny back together, will the pump prime itself? I started the car and got NOTHING in reverse and forward only if I step up the rpms quite a bit. wondering if it's not a pressure issue.
 
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