Possible Tranny Slippage?

[USMC1342]

95 Rodeo 3.2L SOHC, Automatic transmission. I was trying to back out of an icy spot on a slight incline and couldn't do it-rear tires are CRAP. So I threw it in 4WD to try that. The was kind of a CLUNK! feel, and so I turned 4WD off, and went forward as far as I could go (about 2 feet) and got a running start. At this point, the thing started surging on me. Not like an engine surge, btu like the tranny was slipping. At about 2K rpm's it decides it's not going to keep going, and the rpm's drop, speed drops, and then it's like the tranny catches again, the rpm's pick back up, it goes. But when I went around a corner, it seemed like the thing would be able to get about 3K rpms before this happened. The Haynes book says all I should be concerned with is the fluid level, which i will check shortly. What are any/all of the possibilities here? My guess (which is not usually terribly wrong but isn't an expert opinion either) is the torque converter, but I am pretty much just a shadetree mechanic.

[Super 95.5 Rodeo]

Originally Posted by USMC1342

95 Rodeo 3.2L SOHC, Automatic transmission. I was trying to back out of an icy spot on a slight incline and couldn't do it-rear tires are CRAP. So I threw it in 4WD to try that. The was kind of a CLUNK! feel, and so I turned 4WD off, and went forward as far as I could go (about 2 feet) and got a running start. At this point, the thing started surging on me. Not like an engine surge, btu like the tranny was slipping. At about 2K rpm's it decides it's not going to keep going, and the rpm's drop, speed drops, and then it's like the tranny catches again, the rpm's pick back up, it goes. But when I went around a corner, it seemed like the thing would be able to get about 3K rpms before this happened. The Haynes book says all I should be concerned with is the fluid level, which i will check shortly. What are any/all of the possibilities here? My guess (which is not usually terribly wrong but isn't an expert opinion either) is the torque converter, but I am pretty much just a shadetree mechanic.

First of all, after you engaged the 4WD shifter into 4WD, did you first go forward to lock the hubs, then after you disengaged the 4WD to 2WD did you back the vehicle to unlock the hubs. If you didn't do this your hubs may not have engaged or disengaged equally. 95's have a worm gear that locks and unlocks the front wheel hubs. It is not 4WD on the fly.

[USMC1342]

Well, to answer that, I didn't lock the hubs and I didn't unlock them either. BUT......I putt-putted the thing home, posted on here, went out and started it up, threw it in neutral, checked the fluid (perfect according to the Haynes manual), and then decided to run it around the block. It worked perfectly-hasn't faltered or failed since.

Any ideas what this could have been?? I've read on other posts something similar to this involving the transfer case, a sensor, and fluid level. It's fine now so...if it ain't broke, why fix it??? But I want to know what to do if this happens again and doesn't resolve itself.

[Super 95.5 Rodeo]

Originally Posted by USMC1342

Well, to answer that, I didn't lock the hubs and I didn't unlock them either. BUT......I putt-putted the thing home, posted on here, went out and started it up, threw it in neutral, checked the fluid (perfect according to the Haynes manual), and then decided to run it around the block. It worked perfectly-hasn't faltered or failed since.

Any ideas what this could have been?? I've read on other posts something similar to this involving the transfer case, a sensor, and fluid level. It's fine now so...if it ain't broke, why fix it??? But I want to know what to do if this happens again and doesn't resolve itself.

Well, like I said, you have to lock or unlock the hubs on the 95 model year. Almost every 95 4WD rodeo I have seen has semi-automatic locking hubs. By that I mean you don't have to get out of your vehicle and go to the front wheels and manually lock your hubs by turning the lock.

All you have to do is put the 4WD shifter in 4H or 4L and then move the vehicle forward several feet. This causes a worm gear to lock the front hubs. Then the 4WD will be engaged. Your 4WD will not be engaged if you started in reverse first after selecting 4H or 4L.

When you want to come out of 4WD, you must stop the vehicle, shift into 2WD, and then back the vehicle several feet to unlock the hubs.

[USMC1342]

Thanks for the help with the 4WD, but the surging/slipping I felt for the entire 10 mile drive home is the real problem. No grinding, no weird noises....just wouldn't let me go over 2k rpms without slipping/surging. When I got closer to home, I went around a corner and it would get about 3K rpms.....at one point, it did start to get worse, like 1200 rpms. But I parked it, checked the fluid with it in NEUTRAL and it checked out fine. Drove it around the block and there wasn't a thing wrong with it. Any ideas why this may have happened and why it resolved itself? I've read about sensors needing cleaned, transfer cases needing to be engaged properly.......if I have to do anything, I'd like to figure out what before I go searching for any problems. "If it ain't broke, don't fix it" is a good enough credo but this is THE method of transportation so I gotta keep it in good working order. Any ideas/thoughts are greatly appreciated.