My tranny shifts late into 2nd and 3rd then acts as though 3rd is split. It is kinda weak in lower gears but will haul donkeys in the second stage of third, and in fourth. Anyone have good advice on this? (why wont eaton fuller make trans for light trucks?)

 

Sounds like your torque converting locking up.
Custom tuning can change that shift point in a performacne chip, if you want it altered.

 

Plus, if your engine isn't performing right, and not putting out the power it should be, the trans will shift funny because it is "confused" by the inputs the PCM is seeing. I am telling you from experience that if you get the engine running like it should be the shift points will be a lot better. They still won't be as good as with a good set of custom tunes, but they will be a lot better than they are now. Follow me here, the E4OD doesn't have a TSS (Turbine speed sensor) so the PCM looks at things like the throttle pedal position (from the TPS), Boost levels (from the MAP sensor), Back pressure levels (from the EBPS), and uses that along with the speed input form the VSS to determine when the trans should shift. If the PCM is seeing more throttle than expected for the speed and boost levels is sees it holds onto the gear longer because it figures you're towing something of going up a hill (more load on the drivetrain). Ever notice how the truck shifts and drives different when you're towing of going up a hill? This is why it does that. It is holding onto the gear longer so that it can get you going because it thinks the engine is working harder than it should be for an empty truck. Same thing applies when you're accelerating very slowly. It is easy to get the truck to shift before 2,000 RPM when you're taking your time and not really accelerating hard, but mash the pedal and the transmission shifts later because the PCM is seeing more throttle input and knows you're trying to get going faster so it holds the gears longer.

My truck did the exact same thing with the old engine (which was down on power due to injectors that were shot and 400,000 miles on it) but the same transmission, MAP Sensor, VSS, PCM, rear end, everything shifts a LOT smoother now with the new engine in it. It just has the power it is supposed to so the PCM sees the performance out of it that it is programmed to expect.

Figure out why your truck is down on power and the transmission will shift a lot smoother unless your transmission is on the way out.

 

What he said... Mine "shifts" 4 times too... It's just the torque converter locking.

 

I don't think I'll ever miss yelling at my E4OD, commanding it to shift... and it ignoring me.

 

Thanks yall. This truck is getting a bit agrivating, less than 150,000 miles and wont pull my empty gooseneck trailor.

 

Yeah there is something there that definitely isn't right. It should pull that empty trailer like it isn't even back there. I can almost guarantee that the shifting will be a ton better if you can figure out what is going on with the engine.

 

I gave your other post a bump. Hopefully we can get you straightened out.

 

having more power after the converter locks up isn't good.
you may want to consider swapping the converter out before it fails completely (which could take the trans with it,and too common unfortunately.)
example;
Racer X

 

Why is that? I don't understand.

Once the torque converter is at it's coupling point there is no more torque multiplication. There is still slip, and the efficiency of the torque converter is no more than 90%. That means that 10% of the engine's torque is being turned into heat instead of being used to move the truck. If the torque converter locks at this point there suddenly is 10% more torque at the wheels.

 

it's all in the stator.
because the stator should be multiplying the torque and making his truck feel much more powerful when he is claiming the loss.off the line,all through until lockup.or actually yes, when you say it's "coupling point" but this should be up around lock up someplace.not off the line nor all the way up through 3rd.if anything,with a properly working stator,one should feel a loss of performance when the converter locks.

 

I didn't catch that. Loss of performance off the line is probably a bad converter.

 

I didnt relace map sensor yet. It only has power at low rpm. do you kmow how hard exhaust should be blowing? I covered the intake up when idling and it didnt choke motor down. How far can you safely drive with map disconnected? I really want know that the motor problems are electrical. The tranny very well could be a whole other problem. I triedto remove cat, but it wouldnt come off on muffler side.

 

Get that cat off of there, it could be plugged according to what you are saying. You can run it with the map off for a bit, cel will come on, but if it runs better the map is bad or has a plugged/cracked line

 

Do I have to cut it off muffler side?