Hi all. Facing a problem with my '01 1500 with the 5.2. Everything goes smooth in all my gears from a dead stop until 3rd. It misses/stumbles a couple of times and then is fine and then shifts into O/D when it gets to that shift point. If I stand on it to pass it'll drop down in the gears, but just revs wayyy out and won't increase in speed or shift back up until I let off the pedal a lil bit. The revving out portion seems like it stays around 4000 rpm when the pedal is all the way to the floor. I also have it bucking and sputtering in reverse when it's cold and first started. Once it's warmed up, no problem with the reversing, all normal operation. Seems like it doesn't quite have the same get up and go that it used to off the start, almost seems like it builds speed on the slow side. No codes are coming up at all, no check engine light. I've been dealing with this for almost a year now, It's been fine to drive all over, just can't pass anyone cept for maybe the odd tractor that I don't need the extreme power for...lol. This is a real PITA, checked a lot of boards all over and can't seem to find a matching post. I thought when these computer assisted vehicles had a problem it was supposed to tell ya what was wrong! Thinking of saying F--k it and go old school with a 440 six pack. Old school seems a lot easier to diagnose! LMAO....anyways, any ideas at what to look for first would be appreciated.

 

What's been done so far ? Oil and filter ? Band adjustment ? etc ? Any crud in the pan ?

Computers are great for electrical/sensor issues , not mechanical .

 

I'm having a similar problem with passing gear. 1st 2nd 3rd and o/d all work and shift fine, except if im going 120kph in o/d and i floor the gas pedal it will drop to 2nd gear like it should and hold until about 4000rpm. Then its as if it drops in neutral and rpms go way up, i let off the gas and its fine, it goes back into gear. Also sometimes if i floor it from a stop it will be fine in 1st gear, it'll shift to 2nd and when it hits 4000rpm it neutrals and rpms go up. It doesnt do this every time although.

 

Trans pressure sensors are notorious for that type of behavior. (holding gears at WOT) You can replace it, but, that may or may not fix it. Gotta remember, it's a heavy truck, not a muscle car.

Misfiring and such is a separate issue.

 

Nothing trans related has been done so far other than moving the TV cable out a notch to tighten it up a lil bit, truck didn't like it so put it back. This all started as the truck was doing the popping thing in the carb up hills and at the WOT point, so was thinking it was engine related and messing up the revs to hit the proper shift point. Changed out the cam sensor and it smoothed out nicely, but the passing gear issue still remains. Have changed the TPS, an aftermarket that the truck didn't like either. Old one back in now. Hit the cat with a hammer, no marbles rattling around and exhaust pressure at the tailpipe seems to be the same as my other truck, although seems a bit hotter to the touch. It developed an exhaust leak at the passenger side manifold and y pipe, so any pressure should have been somewhat released thru there. Didn't make a difference and the leak is repaired again. forgot to put the stats on this one: is a 2001 5.2 sport 4x4 with about 350,000 km on it. last tune up was about 3 yrs ago and the trans was re-built back in 08 at the dealership.

 

Duh.....forgot to put in there as well....all the thoughts toward engine related was because it finally threw the crank/cam sensor code and an 0351 last week. I've been waiting for something to show up for I don't know how long. Not sure which side to look at, engine sensor fault that is screwing up and sending false info to the trans? or strictly concentrate on the trans and sensors in there causing the problems for engine sensor stuff? Right now there are no codes in the odometer area with the key dance and I don't have a scanner to check any further info.

 

You have two separate issues there. You are going to need to address both problems.

 

now that's a pain, thought these would be related directly with one causing the other. K, so since the engine has smoothed out and running better....where would I begin with the trans? Oil looked okay and was up to proper level when I checked it the other day. And as previously mentioned, the TV cable was tightened up a notch, but to me the truck didn't like the new position and ran worse, so that is back to original spot. Any quick link to do the checks for trans sensors and band adjustment? and is there anything else to check or inspect once I pop the pan off and start digging around?

 

Could be as simple as a restricted oil filter . Like said , it sounds like a pressure issue . No test I know of for the governor pressure switch/solenoid , there should be a code if bad .

If me , I'd drop the pan . Inspect the oil and look for debris . Replace filter and about 5-7qts ATF+4 .
If I noticed correctly on my 96 , there is a check valve in the trans line . I remove these from my Jeeps as soon as I buy them . First was my wife's 5.9 5 yrs ago . Now at almost 200k, it's still shifting perfectly . Her jeep is also tuned , and modified to 325hp ish . Ive done it to several since without issue . I would recommend a trans cooler with this modification if not equipped as the oil circulates pretty fast after .
I also like to install a drain plug in the trans pan when they are out . Makes oil changes easy and dropping the pan so much cleaner to do . They are about $10 tops .
It would be nice to just install new GP switch and solenoid while the pan is off . It is a fairly common failure . Hate to do things twice

 

Well started in on some parts gathering. Both solonoid and sensor comes up to 320 at the stealership, get those tomorrow. Hate those guys. Got the filter and gasket, hopefully they are the proper ones. Checked into the aftermarket drain plug, must be an american thing cause the different parts places I stopped in at all looked at me sideways when I asked about it (north of the border here)...lol. Oh well, have to maybe get ahold of a tig welder and make my own! Interesting thing that I noticed when I was out. I paid a little more closer attention to the shift patterns and noticed that I don't have to be at WOT for anything to start acting up. Found that I can get it to start bucking at maybe three quarters throttle, almost feels related to the TV cable position. Now question here is, what are the parts in the trans that are related to TV position? Dunno if this changes the way of thinking or if it starts to point more towards a specific area.