Join Date: Nov 2018
Feedback Score: 0 reviews
4r100 trans issue. 4th gear woos
I've got an issue with trans not shifting properly. This is a Ford reman trans with 180xxx. I would think any updates would have been put in at this time. Like the ratchet style drum, etc. 1st Problem: summer. After an HR of stop an go traffic jam, and finally getting to get back to 70, I had a slip in OD. At 1st I thought TCC as it was slipping and only increasing in rpm about 300. I promptly turned OD off and drove 60mph the rest of the way home, about 35 miles. On the way I got ahold of a good friend to see about using his maxisys.
The next day I plugged it in and everything looked fine. SSA and SSB were working properly. TCC was locking up at 156% (as per chip). TC slip actual vs desired pre lock and lock we're all just fine. The truck ran and shifted great. Was able to do full on pulls in 4th with out issues. After talking to my buddy we decided TC got heat soaked and was just 'one of those things'. Everything was great for about 5 weeks. Then, it happened again. This time on my way into work in the AM. After 45miles of driving it was slipping. Seems how it was on 50* outside, I thought for sure it wasn't a heat soaked issue. Trans temp itself was about 168* as per the maxisys808. I immediately checked the live data. To my surprise nothing looked off. Only thing I DID notice was converter slip. When locked it was calling for zero slip and actual was varying between 0-11 RPM, yes, Eleven. And this was at 65mph. At the end of day when I left to head home, it was fine. And all the live data looked good.
It was fine up until about 4 weeks ago today. Same symptoms presented. Have not been able to run the maxisys as I don't have it 🤷. Took to a trusted trans guy and he went for a ride with his snap on modus. He didn't realize anything was wrong because he was looking at scanner. I had to point out to him what was happening. He said it wasn't TCC and the solenoids were working as should. TC slip actual vs desired he said we're right on spec. He suggested the TC had scored the pump. That it would need a new billet TC, pump and bushing, that the mechanical diode had failed and would need new OD clutches. 🤦🤷.
Upon further driving and doing my best to isolate the issue I've found these things.
With chip installed: any position causes the OD light to blink eventually. Generally about 5-7 tries of it attempting the shift to OD. Before the light trips, it will only shift to 4th if your going down hill and give just enough throttle to prevent coasting or engine braking. Any amount of throttle over these scenarios instantly drops out of 4th. I've also confirmed that the rpms at which this condition occurs is a match for 3rd gear with lockup. So another verification of TCC working.
When I get the OD to start flashing it will now go into 4th gear. This only happens in chip position 5,6. It will shift into 4th and as long as I accelerate easy and not too much of a grade, it will hold 4th. No slipping.... just runs as it should. Chip positions stock,2,3,4 will allow it to shift into 4th but can not hold it in any circumstance other than down hills or a fuzz above coasting.
Last thing: decided to pull ts6 chip. Now that the truck is gutless I was able to find out that it will (driving easy or normally) shift into 4th at 24% engine load. This would be going thru gears nice and easy. This would be flat road with very slight hill. At 25% load it drops out of 4th into 3rd with lockup. How do I know? I set cruise right before it downshifts. I then note the RPM then turn OD off. Rpms obviously increase, but come back down when TCC locks up. And the rpms match from when it dropped out of 4th to begin with.
Ok, now I'm running about 50mph. I'm in 3rd with lockup. I accelerate easy but steadily. Turn OD on. Continue to accelerate. At 70% engine load it will then upshift to 4th. I continue to accelerate, more aggressively now up to 90mph. 4th never slips once. I gradually slow down. Not full release of throttle, but just an easy backing down. It gets down to 50% engine load and shifts back to 3rd with lockup. I again can bring it back up to 65-70% load and process repeats.
I have engine braking in 4th in any scenario of chip, no chip, chip position etc. For example. If I've crested a hill about 45mph and have had an engine load of 24%(where it will shift) then come down hill foot off throttle 100%, I have full engine braking from 4th gear. It unlocks around 40 mph
If I'm in 3rd above 30mph and 1k rpm and lift off throttle, it will brake down to 30mph @1k rpm.
Engine braking in reverse is also working.
Truck is 01. Reman Ford trans. Not sure if it's actually a Ford or Jasper but work was done at Ford dealer.
I've been pm'ing Mark K. And he's been very helpful, as you all know 🍻
But wanted to see what the rest of the community thinks. Also wanted to take this from a pm to open for when the next guy/gal has this he/she can look through to see if it'll help them.