primalurges

dropping the pan allows you to replace 6 quarts. More than half of that will remain in torque convertor. I'm done with flushing because I've already been told that my clutches are shot so continued flushing will only make matters worse. The Lucas essentially increases ATF viscosity thus increasing band pressure to stop or limit clutch slip.

papa tiger

So UR ready for the inevitable ?

dixiemudder4x4

I need to update. I dropped the pan and valve body. Finding nothing wrong I decide to pull the transmission. I tore it down and found the forward clutch pack smoked. I now understand why I had the symptoms I did. The forward clutch is not a shifting clutch. It comes in when shifting into drive and stays in until over drive. This explains why manually shifting from OD would take so long.

After much reading I decided to attempt the rebuild myself. A few months later my truck is back on the road (I did research and decided to hold off until after Christmas). I have about $650 into the rebuild, one day out, one to rebuild and one to install. I found a cut seal in the forward clutch piston which I believe was the cause of the failure. Inside the case was very clean. I'm glad I chose to park the truck rather than continue driving it.

This transmission is very easy to rebuild a clutch spring compressor was the only special tool I needed. I completed the j-mod and really like the feel of the shifting. I also installed the sonnax sure cure kit. This "freshens" up the valve body and addresses a couple issues. I learned that boosting line pressure via a tuner is not a good idea. It causes premature wear of the pump and stresses the drive train probably why my sun gear cracked a tooth.


Rebuild kit $190
Bearing kit $50
Pump and tail shaft bushing $10
Bands $45
Sun gear shell $85
Torque converter $150
Sonnax sure cure kit $100

primalurges

Good to hear you tackled the rebuild and resolved your problem. I've been battling this with Lucas stop slip. I've clocked about 11k miles since my problem started. Second to third is a little hard sometimes but much improved since when I first noticed the problem.

dixiemudder4x4

Since forward stays engaged through gears 1-3 and releases for 4th you shouldn't be putting full torque to it until you do a power on down shift to 3rd. I would drive it carefully and limit the throttle when downshifting. The other thing is if the clutch material is gone from the plates it is still mixed in the oil. Changing the oil could make your problem worse.

David Jaynes

Wow, I am so impressed with your DIY transmission project. I have always thought I was a pretty competent DIY mechanic, but AT work has always been a bit scary to tackle. I have done complete engine rebuilding, but the inside of an automatic transmission seems like magic to me. Did you find a manual somewhere to give you all the details to tackle this job. I would like to rebuild mine in the future, but I need more info to take the mystery out of the job. I bought my 150 with about 70,000 miles on it and the transmission seems to work well except for a slow engagement in reverse (has done it since I got it and hasn't really changed in severity even though I now have 125,000 on it). I changed the filter and just the fluid that was lost with the pan drop at 80,000 miles with no change. I am fairly confident that I am the only person to have opened it up since the dipstick hole plug was in the pan when I took it down.

dixiemudder4x4

I got two manuals from Transtar which is my local supply retailer. One was the service manual and the other is the update manual. Believe it or not the 4r75e is based off the AOD and AODE transmission from the '80's. Where you will find the majority of information is if you look for the 4r70w. The update manual explains what was changed for the 75e (mainly adding a second speed sensor and changing a couple internal components.

I work on heavy equipment for a living and consider myself a good mechanic but like you would shy away from the internals. The alternative in this case was a $4000 unit from Ford or aftermarket for around $2000. There is a very informative video online of this very rebuild, after watching it the job didn't look as difficult. My truck had 43,000 miles on it so valve body wear wasn't much concern for me. This is the area I would be most concerned with if your transmission fails and you cannot pinpoint a cause or if it is high mileage. The Sonnax sure cure kit addresses many of the common areas of wear so do your research first. Take your time installing sealing rings and clutch piston lip seals and keep everything clean.

If you are interested in modifying the performance of the shifts look for information on the "j-mod". There is a thunderbird forum with a lot of useful information on the subject. I believe there is a hole in the separator plate which can be enlarged to address the slow rev engagement. I opened mine and the transition is very quick now.

m5james

Bumping this thread due to having some good info and similar symptoms to my 2002 HD F150. I had the trans rebuilt about 4yrs ago but at this point I think they didn't do anything more than a trans flush and the truck has been getting slowly worse and worse.

If it sits parked for more than a week, reverse is almost non existent...it'll rev but hardly move. It's ALWAYS been slow to shift into reverse, enough so where I'll roll forward on an incline until it finally kicks in and even then the truck will shudder when backing up so I've gotta two feet it most times because it'll go from slow/slipping to jumping.

Going into drive has always been fine other than it'll slam doing 1-2 shifts and even 2-3 shifts, so much so that I've learned to just let off the gas when it's about to shift to prevent the SC belt from chirping and/or the truck feeling like it's being rear ended. I've also learned to shift into neutral at lights since the RPM will jump, which feels like it's falling in and out of gear and/or will just kill the truck. Oddly I can unplug my BA2600 MAF and it'll shift smooth as butter, but then I can't get into boost. MAF tests out fine and did the exact same thing using my buddies MAF who has practically the same build.
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Newest and latest issue as of last night is it started slipping while cruising down the highway...went from 2k to 3k and then fell back down to 2k with a slight jolt. Oddly I could punch it and it was fine, it only seemed to happen while cruising.

I bought a used trans a few months ago for $500 in anticipation of this day, but I'm torn between trying to fix the current one before swapping and/or taking the best from both trans to make one solid one. Anyone happen to have a direct link to the upgrade/rebuild kits mentioned above for a 2WD 4R100? I've tried looking but it's borderline confusing. I've already got a 4WD trans pan to install as well.

ssmobile

Replace the 2-3 accumulator with a bullet aluminum, it's allowing fluid to bypass and causing line pressure drop. It will cause delayed shift into forward and sluggish shifts. If you want to firm up your shift leave the bottom spring out it gives er a nice firm shift and saves problems later.