aw4 tranny question

I have a 91 xj laredo with aw4 tranny. The tranny works fine until it gets fully warmed, then it starts to waiver between 3rd and 4th. After a bit it won't shift to 4th at all. I was told that the solenoid is probably going bad. Does that sound right? If it is, do I have to drop the tranny, or can I get to it while it's still on. Where is that at even? Thanks for the help.

I'd start by checking out the TPS sensor as that's the usual culprit for erratic shifting. You might also check the brake switch, which if it's dirty or misadjusted can cause the torque converter to unlock/lock erraticly (might seem like it's downshifting).

Thanks, didn't think about the brake switch. I replaced the "anti-stop" brakes and had to do some pedal adjustments for it to work. The brake lights don't alway shut off, so that might be a good start.

I don't think its the solenoids cause when the trans is in 4th both solenoid 1 and 2 are off so it seems like you would get stuck in 4th if they went bad.

How old is your tranny fluid? If it's at all old, or if you've possibly overheated the tranny during the life of your current fluid (in whick case it will smell "burnt" if you drain some), you might start with a full flush and replacement of fluid.

Mine did it when my Torque convertor went dead, might just need a tranny flush/filter change though

I dinked with the brake switch when I got off of shift this morning and not only did it shift right, the cruise control works. The clip wasn't holding the switch all the way in so it was opening every now and again. That explains a lot of dirty looks and getting the finger a lot when I couldn't figure out what I had done to upset them. Either that or I drive like I'm in my big red truck. I don't know. Thanks to everyone for the ideas. Late.