42RE rebuild

[rob92xj]

Turning the line pressure up really does nothing with a RE trans except messing up the controller. The shift quality is controlled by the electronic governor and governor pressure transducer readings. So backing the line pressure back down to the factory setting might fix your problem.

[death-mobile]

I'll try it. Sucks to drop the pan again after just changing the fluid. Gotta make some clean containers...

If this is the case...why don't other people that put the transgo shift kit into other 42RE's have this problem? They suggest bumping the line pressure up to their spec...not factory.

[rob92xj]

The instructions are actual a copy and paste from the instructions for a RH series transmission. When I installed the Transgo shift kit in a friend of mine trans and the 46RE in my Ram I left the line pressure where it was set at the factory.

[death-mobile]

Do you remember how far from the plate the spring was? I know what the factory spec is, but I'm curious if you remember visually.

Has anyone else had trouble with a P1763 code on a 42RE with an altered valve body? I would be one happy son of b*tch if the line pressure is just too high.

[rob92xj]

It has been awhile since I had to go through a 42 RE valvebody since our biggest problem these days are the NAG transmissions behind the 3.7L in the WK and XK's as well as the 5.7L & 6.1L Hemi's in the LX cars.

[death-mobile]

either way, i'll just back the pressure down to spec and see what it does.

[UTChavok]

So howd it turn out with the line pressure?

My 42re is in need of a rebuild and all shops around here want $1500. I have 0 transmission experience but am thinking about buying one from a junkyard and swapping it in, then rebuilding mine while its out. I have some friends in our club and what not who have messed with transmissions, not sure if anyones done a full rebuild though.

[death-mobile]

haven't changed the line pressure setting yet, been too lazy to drop the pan again since I just changed the fluid. i'll get around to it soon though...right now when the light comes on, I just turn the jeep off at the first stop sign or light I get to and the jeep is back out of limp mode.

the only reason I've been putting off backing the line pressure down is because I have a bad feeling that it isn't going to fix anything. but i'm trying to be positive!

[1v6pony]

Although I have the 46rh what else did you do to remove the overdirve unit??
I have removed the parking pawl attached to the valve body, the bolts in the case and spread the snap ring under the cover but it does not want to seperate past apx 5/16 of an inch...it will wiggle right to left just wont come apart... Do I just need to hammer the crap out of it???

Thanks

[nate]

In my experiences, that is not true at all. Increasing the line pressure increases the pressure applied to the clutches preventing them from slipping. VERY VERY VERY important on a trans that is powered by something with some HP.

It's not a big deal on a stockish 4.0L, but it really makes a difference in the diesel world.

Yes it can mess with the electronics of the trans, but that is fixable.

Turning the line pressure up really does nothing with a RE trans except messing up the controller. The shift quality is controlled by the electronic governor and governor pressure transducer readings. So backing the line pressure back down to the factory setting might fix your problem.

[death-mobile]

fixable? such as putting a 150ohm resistor inline with the trans signal wire?

I did that and it didn't do a damn thing. My next move is to back it down to the stock setting, but I haven't gotten around to it yet. This is the most annoying thing in the world...perfect trans, until the CEL comes on.

[indy242003]

I really wish I could help you here, but I run the same kit in my valve body with no codes and it shifts hard with no issues. I replaced every bit of the electrical stuff in the valve body though. I was so done with it before I was done and I really did not want to go in there again.

[death-mobile]

It must be something APS did with the valve body. I tried to save some time and had APS send me a new body with the kit and whatever tweaks they do. I'm fairly sure they got it all shitted up and they haven't answered my calls in over a year...soo...F them.

I'm going to back the pressure down, and if it doesn't work, I'm just going to get a stock TB and build it up with the same kit and leave it at that.

I was wondering, when you are cruising around town, and you are in 1st, do you ever speed up enough where the trans is sooooo close to going into second, and then you let off it and it recoils and sounds pretty rough? That's something else that bothers me, but as long as I don't let off the throttle, it will move into 2nd smoothly. I attribute that to one of APS's tweaks as well. I think the body is just overworked. Hopefully lower pressures will fix the CEL.

[indy242003]

I was wondering, when you are cruising around town, and you are in 1st, do you ever speed up enough where the trans is sooooo close to going into second, and then you let off it and it recoils and sounds pretty rough? That's something else that bothers me, but as long as I don't let off the throttle, it will move into 2nd smoothly. I attribute that to one of APS's tweaks as well. I think the body is just overworked. Hopefully lower pressures will fix the CEL.

No, when it winds up close to shifting, if I let off it shifts hard into second. I'm not sure exactly what they did, but it for sure does not sound right. Call these guys http://www.transmissioncenter.net/highperflist.htm . They were a big help when I did mine.

[death-mobile]

I don't know if it is falling back into first, or slamming hard into 2nd...it's kinda hard to tell. Does that place take tech calls? I just looked at the site and it seems like they might not give out free advice

[zjrog]

Glad I saw this thread... I might rehab a 42RE for my 95 ZJ this summer. I'm finishing a Ford A4LD for an Explorer and we'll see how I did soon...

[indy242003]

I don't know if it is falling back into first, or slamming hard into 2nd...it's kinda hard to tell. Does that place take tech calls? I just looked at the site and it seems like they might not give out free advice

Yep they do. Just ask to talk to the shop.

[death-mobile]

UPDATE


...so far so good. I backed down the line pressure A LOT. I went with the factory spec of 1" 5/16 but it made noooooo sense. Measuring from the body to the spring seat is far less than 1 inch, so I threw that notion out the window and checked the internet. Seems a lot of people went with backing it down flush with the spring as long as possible, and then turning it in 2 turns. They say if you go more than 2 turns, a 150ohm resistor is needed inline. I went with almost 2 full turns and left the resistor in place.

First of all...that "clunk" I spoke of before was a driveshaft noise. When the trans was getting ready to shift but the throttle was backed down, it would shock the driveline because it was set for such intense shifts. It was great if you were going balls-out everyday, but for a streetable rig, too extreme is a bad thing. So far, that has gone away and the P1693 has seemed to stay away so far. I haven't taken it on the highway so that is the big test. If it comes back...I'm ripping the valve body out and sending it back to APS with a note that says "you suck".


Building from nothing and using manuals is much easier than fixing someone elses dumb mistakes. I should have just modified the stock valve body myself. I thought I was getting something special by ordering one of these fancy tweeked valve bodies.

[the peps]

hello guys, i write from italy and on my 95 4.0 zj have a problem with the trans..
it has gone in limp mode, the od light stays on all the time and there is no shifting, downshifting or anything else. i am using it like a manual shift. the speed sensor has been changed, the oil and filter too and nothing change. there was some debris in the filter, and now i am decided to change the solenoid/sensor inside the box. any advice??
thanks a lot in advance...

[cavaliers1323]

all in all, how much do you have in the rebuild? And was the only tool you bought the clutch pack tool? Do you think you would have been better off with the higher dollar kit or was the ebay just fine? Maybe a parts list price breakdown! Seems a lot of us are on edge about dong a rebuild, I just wanna get everything together and have t ready to go in as soon as I pull the trans. My zj is my only vehicle, and I don't have any 42re sitting around.

[iluvtruenos]

Did your trans hunt between first and second gear when accelerating slowly when cold?

If so, what did you do to solve this? Did you reuse all your old electronics and just replaced hardware, or how did you go about fixing this problem?

Mine will shift fine if I apply anything over 25% throttle.

[cavaliers1323]

Have you tried a different resistor?

[death-mobile]

A different resistor? Such as...?

I'm going insane with this. Maybe there is a short somewhere, and I just can't find it, but I find it hard to believe that only after I rebuild it, that I get this CEL. It seems to be random now. I can usually make it come on when I go onto certain hills around town...over 55mph. The other day, it didn't come on at all in a 75 mile drive, highway and around town.

I thought about the TSB for an errroneous P1763, but, my jeep is a 2000, so technically it should already have the new software for higher pressures, even if the valve body APS used was from 97 or something.

Does the TPS wiring have anything to do with P1763? I got some more info on it and someone suggested the throttle pressure cable being out of adjustment. If the cable binds, perhaps it could cause the CEL to come on for the P1763??

Possible reasons for P1763...

5 VOLT SUPPLY CIRCUIT OPEN

GOV PRESS SENSOR SIGNAL CKT SHORT TO VOLTAGE

GOV PRESSURE SENSOR SIGNAL CIRCUIT OPEN

SENSOR GROUND CIRCUIT OPEN

INTERMITTENT PROBLEM

OTHER TRANSMISSION DTC'S PRESENT

PARK NEUTRAL DTC'S PRESENT

TRANSMISSION FLUID LEVEL AND CONDITION

GOV PRESS SENSOR SIGNAL CKT SHORT TO VOLTAGE INSIDE TRANS

5 VOLT SUPPLY CIRCUIT OPEN INSIDE TRANS

GOV PRESS SENSOR SIGNAL CKT OPEN INSIDE TRANS

GOV PRESS SENSOR GROUND CKT OPEN INSIDE TRANS

GOVERNOR PRESSURE SENSOR (HIGH)


I'll go over the connections again, check the round connector at the trans, maybe back line pressure down again...but I dunno. I don't think it's a short because of the fact that it doesn't matter how bad you shake the jeep, it only happens when it's under a load.

[cavaliers1323]

Have you tested the resistor to verify it's working?

[death-mobile]

It's the resistor that was recommended, but honestly, no. I haven't put a meter on it. I never heard of a resistor not working before...but maybe it's worth a shot to put a different brand on it.