Need tranny help

I have a 93 rodeo 3.2 V6 4x4 4L30-E trans. I got a used trans. from salavage yard put in it and now it is hard to take off in drive but if i put in Low and manually shift up it does fine. The mechanic who put it in says it could be the EPC seloniod in the valve body. Does anyone have any ideas.

I have a 93 rodeo 3.2 V6 4x4 4L30-E trans. I got a used trans. from salavage yard put in it and now it is hard to take off in drive but if i put in Low and manually shift up it does fine. The mechanic who put it in says it could be the EPC seloniod in the valve body. Does anyone have any ideas.

these are 2 wild arse quesses based on the sketchy info available

* it is starting off in Winter Mode. Winter Mode starts you off in 3rd when the gear selector is in D Drive. it's so you don't over torque the rear end and skid out as you get under way. normally this mode is only selected if you push in the Winter button. somehow that mode is being selected all the time. cause ? perhaps a connector or two were hooked up wrong ?

**the gear selector mode switch (also called sensor) is malfunctioning. (( this "mode" is NOT the same as the above Winter Mode above, they are two completely seperate things)) the gear mode sensor/switch essentially tells the trans computer what gear you have selected, and the trans computer than tells the electronic part of the automatic transmission what to do. when the mode sensor malfunctions it gives the wrong info to the trans computer and the trans gets confused because it's in one particular gear and the trans computer is telling it, it's in a different one. BUT usually there are other symptoms tipping you off to this problem -- e.g. the gear selector lights don't jive with the actual gear selector position, and/or harsh upshifting in particular between 2nd and 3rd, often.

frankly, i don't know what an ""EPC seloniod in the valve body"" is; so i can't say if your mechanic is whistling in the dark for sure or not. but i'd be more inclined to follow the first guess above, and see if further observation leads to that.


hth

//bc

We dont think it is in winter mode. i drove it back home from the shop its about a 45 min drive and i was going 60 and the winter mode kicks off at 30 and i have hit the button several times. We bought this vehicle in Aug. and its is our first time driving it. The last transmission in it would get locked in reverse then not go so i am not sure it iam actully doing the winter mode button correct but i read the manual and winter mode is spossed to go off after you reach 30 miles per hour. I hope we can get it fixed soon and not out much more money.

...winter mode is spossed to go off after you reach 30 miles per hour. I hope we can get it fixed soon and not out much more money.

exactly -- spossed to. it should be easy enough to check with dvom whether the trans computer is getting the winter mode signal. and it's way easier than the other alternative.
i would test this and get ruled out first. imo.

//bc

P.S. any other symptoms etc that you can tell us?

I got the alternator checked today and its charging at 17 volts so we are going to put a new one on tomorrow. I tried winter mode and it is not working at all, the light doesn't even come on. Tried the power mode and the light comes on but nothing happens. Hopefully changing the alt. will fix it. Also after you drive it for a few minutes and reach about 45 MPH the check engine light comes on then goes off when you have to sit at a stop light.

I got the alternator checked today and its charging at 17 volts....

good call on checking out the alternator. it can cause all sorts of seemingly unrelated problems when it's not charging correctly. especially when it's not charging enough, it can cause weird responses from the automatic transmission.

i haven't heard of your symptoms being alternator-related (...yet). and you didn't mention anything about your volt meter running high -- is it?

thanks for the follow-ups


//bc

We changed the alternator today and everything is fixed, including winter mode works now. The alternator was putting too much voltage out, it is only supposed to put out about 13 volts. Who would of ever thought. Now we are wondering if we needed to put another transmission in in the first place. Thank you for all your help.

What were the symptoms before the first swap?

The transmission would lock up in reverse but only sometimes. We do not know alot about this rodeo because we bought through EBay for $750.00 in Aug. I guess we are learning as we go on this vehicle.Everything seems to be going ok now but i know if anything goes wrong with it we are going to check the ALTERNATOR first

Yes, these trucks will act VERY weird if that alternator - or any voltage is either low or high.

What alternator did you put in?

It's very important that you didn't use just any regular parts store alternator, these trucks seem to eat up the reman alt's, and usually spit them out within 3-4 mnths.

I got an Alt from Advance auto with lifetime warranty for $135.00. So i guess we will see who this one does and go from their

My reman from Advance didn't make it around the block. Good luck with yours, though!

leafadawn: since you are still checking in on this thread --

did you notice when you were having the trans problems, was your dash volt meter gauge showing overcharging?

thanks

//bc

When i noticed the meter it was showing overcharging but that was after we put the new transmission in. When we bought the rodeo the guy told us it need a new transmission or computer because it was locking up in reverse so we bought a computer off ebay for $35 changed that and it still did the same thing so we decided to get a transmission. After we got the new transmission in it is was not switching gears. So we did more research on the internet and found a site where it said check the ALt so we did it was over charging and we changed it. Everything is working great now so i guess we learned our lesson on this one but my husband and i were so frustrated we never looked at the voltage till it was too late and we put all that money in it but hey i got my car running so i guess it cant be that bad