Mikey89014
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Also, my reverse slips unless I increase the TPS voltage. Thank You
6.9 Superduty
- Thread starter Mikey89014
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Also, my reverse slips unless I increase the TPS voltage. Thank You
Mikey89014
Full Access Member
Do you think it could be a valve or broken spring? I double checked my check balls with a pic I took on rebuild.
trackspeeder
Stone crusher.
Take a look at the accumulator valve. That could be sticking on you.
By increasing the TPS voltage opens the EPS increasing line pressure. This is how Banks and others "improve" performance of the E4 electronically.
Did you add a shift kit? Such as TransGo. Your ball locations will vary. That could cause issues too.
By increasing the TPS voltage opens the EPS increasing line pressure. This is how Banks and others "improve" performance of the E4 electronically.
Did you add a shift kit? Such as TransGo. Your ball locations will vary. That could cause issues too.
Mikey89014
Full Access Member
No shift kit, just an upgraded steel boost valve, steel planets, eliminated wave plates, etc. for more discs, 6 clutch reverse and 3 overdrive clutches. I also installed the sonnax spiral od ring and spacer between case and center support. Also snap ring for center support upgrade and rubber tubes between center support and case to prevent leaks. Thats about all..
trackspeeder
Stone crusher.
You should add a shift kit to your tranny. Take advantage of your work.
Take a look at the accumulator valve.
There is a possibility that you are setting the TPS voltage to low. This will throw off the EPS, dropping line pressure.
Take a look at the accumulator valve.
There is a possibility that you are setting the TPS voltage to low. This will throw off the EPS, dropping line pressure.
Mikey89014
Full Access Member
You should add a shift kit to your tranny. Take advantage of your work.
Take a look at the accumulator valve.
There is a possibility that you are setting the TPS voltage to low. This will throw off the EPS, dropping line pressure.
Yeah , but as of now , with all those updates , it shifts very solid through all 4.
If I install the TPS the correct way, it ups the shift schedule to a very high RPM as the TPS opens. Right now i just have it disconnected from the pump and just sitting there at the lowest setting. My RPM is kinda low now for the shifts, but not unbearable and manual 1 works correctly with it just set at a low voltage. However, with a high TPS voltage, my reverse doesn't slip.
I may have to double check the valve body. I'm just afraid to pull it down and have more stripped valve body bolt holes when I go to torque it back down. I must have repaired 3/4 of the valve body threads even with proper torque applied.
I have a feeling the previous builder used a an impact of sort to tighten the valve body. Even half the pump and most of the pan bolts were stripped on this thing, I'm not joking.. I had to make a jig to install the helicoils properly and straight.
david85
Full Access Member
What are your TPS voltages exactly?
If it shifts well, I wouldn't bother with a shift kit. More friction material accomplishes the same goal without adding more line pressure.
Sorry to hear about the stripped holes. I learned that lesson when working on mine. I ended up gluing some 6mm ready rod studs into the damaged holes. Tried 5 min epoxy and it worked well by softened at 200F. JB weld seemed to hold at that temperature and above (bench tested on a spare section of valve body casting). So far no problems and I've had the valve body out a few times since then.
Mikey89014
Full Access Member
I set it for 1 volt idle and roughly 4 open , and even at that setting it shifts at a very high rpm with just a cruise and not much pedal.
I dont like to mention any names , but the first 6 initials of the last builder begin with Jasper.
I dont like to mention any names , but the first 6 initials of the last builder begin with Jasper.
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david85
Full Access Member
The only theories I can come up with at this point are:
1: Valve sticking (as trackspeeder already mentioned)
2: Air could be either getting into the hydraulic circuit, or hasn't been purged yet. Cycling from each gear selector position several times may solve this problem. However if valve body bolts are indeed damaged and not clamping well enough (or some were overtightened), that can also cause malfunction of the spool valves or accumulators. Sometimes scratched or nicked valves will behave differently when the transmission is hot vs cold.
3: Since this is a modified setup, it could be your PCM is expecting some information from the OEM V10 setup that it isn't seeing. You already mentioned the lack of a turbine sensor. I can't be too sure here, but maybe this, or another missing sensor input is causing the problem.
Oddly enough, I can't say I noticed much difference in reverse engagement when my Baumann TCM is unplugged. Its been a while since I ran it like that though.
Did you ever notice soft, or weak reverse engagement when the solenoid body plug was unhooked?
trackspeeder
Stone crusher.
Adding more friction beefs up the clutch pack. It doesn't have anything to do with line pressure. Increasing the line pressure guarantees the clutch pack is going to hold. The catch is not going to far with it. To much is going to break stuff. To little will burn up the packs.
The shift kit will allow the proper use of M1 and M2 and firm up where needed.
Mikey89014
Full Access Member
Yes, reverse is great unplugged, and M1 doesnt work unplugged or with a high 4v TPS, only idle TPS allows M1 to work ok. Thanks
david85
Full Access Member
I didn't say friction material surface area affected line pressure. I was referring to shift firmness.
More friction area for the same line pressure will firm up the shift.
Similarly, more line pressure for the same friction area will also firm up the shift.
Both together will multiply the effect.
More line pressure is easy to accomplish but adds more stress to the hydraulic systems (cracked converter lockup piston can happen even at stock setting). It also increases shearing stress per square inch of friction material. I prefer adding more friction material (more clutches in the clutch packs) but obviously that's a lot harder to do than simply upping the line pressure (either via the EPC or valve body mods).
Sorry for the OT...
Mikey89014
Full Access Member
Forward gears are solid with low or high TPS voltage , but reverse needs at least 2 volts of voltage or it slips up hill in reverse. I'm not sure why , I added and extra clutch to reverse as well and 5 direct with HD drum.
david85
Full Access Member
If I'm following correctly, you're running the Superduty PCM that was originally intended for the V10, right?
I still can't help but wonder if something is different in the superduty 4R100 control strategy compared to the E4OD.
The EPC is not directly controlled by the TPS. The PCM (TCM) takes signals in from all the sensors, including the TPS voltage and uses this information to vary output of the EPC.
From what I've been able to find, the EPC is current controlled, not voltage controlled. Even still, I wonder if it would be possible to probe the EPC wire at the solenoid body to see if the readings are indeed different between 1st gear and R gear (for 1V TPS idle setting). That could narrow down the issue to electronic. If however, the reading is indeed the same for 1V TPS idle setting in either 1st gear or reverse gear, the problem would have to be somewhere else (valve body or even internal hard parts of the trans).
I still can't help but wonder if something is different in the superduty 4R100 control strategy compared to the E4OD.
The EPC is not directly controlled by the TPS. The PCM (TCM) takes signals in from all the sensors, including the TPS voltage and uses this information to vary output of the EPC.
From what I've been able to find, the EPC is current controlled, not voltage controlled. Even still, I wonder if it would be possible to probe the EPC wire at the solenoid body to see if the readings are indeed different between 1st gear and R gear (for 1V TPS idle setting). That could narrow down the issue to electronic. If however, the reading is indeed the same for 1V TPS idle setting in either 1st gear or reverse gear, the problem would have to be somewhere else (valve body or even internal hard parts of the trans).
Mikey89014
Full Access Member
I believe it is EPC yes because unplugged (where EPC is high) reverse works great but MAN 1 drags. plugged in the EPC is low because of TPS . This makes my reverse slip and MAN 1 work properly unless I increase TPS(step on the gas). But, the increase TPS raises my shift schedule way too high as well and ties up MAN 1 with another gear or whatever it is.. I don't use MAN 1 anyways but the error is still there raising my shift schedule too high as well as a slight bind in drive starting in first, but this clears up on its own after a second..
