87 Cherokee Auto Tranny wont Engage??

[ody]

i posed the same question on another forum 4 days ago with no response (not automativeforums.com). i am hoping to get some feedback here as it seems to be more active 8)

1987 jeep Cherokee, 193K miles. My (floor mounted shifter) automatic transmission seems to be failing. Here is my sympotms:

Reverse works with no problems. i put the it in Rev and off i go.
I put it in (D)rive and nothing (it got progressivly worse until now). I rev
the engine up to about 3500-4000 rpm for a good 5-10sec and then it starts creeping untill finally (slowly but surely) i get up to 25-30mph when it kicks into 3rd. After 3rd gear it has no problem going into and out of 4th gear. It is only when i start of in 1st gear that it wont engage. Same with L1 and L2. Although at first i was having luck with L1. To start off i would slip it into L1, it would engage and get going then switch it over to D at around 20mph. smooth transition to 2nd and 3rd. But lately even L1 wont help.

Jeep was and still is running smooth. the engine idles very good and like i said, after getting up to speed, 40mph+ the tranny has no problems. it engages overdrive, and shifts down when i hit the accelerator hard.

my jeep has 192K miles, is it just due? Although like i said, 3rd and 4th
gear seem pretty smooth. I thought maybe i was loosing vacuum or ??? but i did a quick check under the tranny and couldnt see any obvious signs of something going wrong (loose, wet or otherwise).

in reading much information on the internet, i will be cleaning my throttle body and inspecting my TPS. I also bought a TPS for $70, but will try the cleaning first and see if thats the culprit. Is there a way to check if the TPS is actually working???

thanks in advance for any help,
-O

[MagicRat]

For some reason your clutch packs for the first and second gears are either not getting enough hydraulic pressue or are leaking pressure and are slipping.
Do not drive your jeep. Slipping clutches in a transmission can wear themselves out completely in just a few miles and will require a rebuild to fix.

Replace the trans fluid and filter and wash out the pan. The filter could be so badly clogged it will not allow enough fluid to pass.
In my experience, this will fix the problem about 60% of the time. If it doesn't you likely have internal problems and need a complete rebuild.


I had a '77 Caprice with this problem. When all forward gears let go, I had to drive 5 miles home in reverse.......(at 3 am)