No foreward motion in any gear- Input NEEDED.

I have a '89 laredo with an 4.0, aw-4, np242 case. My problem is I bought this jeep broken and the previous owner drove it everyday. They were on the freeway and heard a pop, the jeep died, and now there is no foreward or reverse gear. Nothing in 4wd either. I pulled the rear shaft to see if the tail stock is turning and it is turning. The shaft turns slower when the gas is applied and goes into reverse when put in reverse. I dropped the trans pan and everything looks good to me. No clutch media and fluid is not burnt. I started to remove the trans and was thinking it may be something else. Could it be the T-case? Could it be the torque converter? Could the trans not be gettin line pressure? I really need help here. Thanks!

If the tail shaft on th tcase is turning then its not the transmission. I would pull the tcase though. It's easier to replace and check to see if the out put on the trans is turning. If it is bench check the tcase.

Ok will do. It slows down when throttle is applied. Ill pull the case. Any way to check the t-case without splitting the case?

Hummor me here, check the vacuum line from the throttle body to the MAP sensor, see if it came loose during a backfire. It is common, and your description is a little vague, so lets start with an easy check.

If it can't get over 1500 rpm in park, there is sensor problem before the TC.

Engine runs fine and there is no problem revving. Ill check the vac line when I get home from work tho. Could it be a t-case chain? Also thought it could be a pressure line in the trans that came loose. Ask me any questions to help clear things up. Sorry for the vague discription im not sure how to explain it or diag it. Thank you!!

The chain is only used to drive the front output

I would say the pump in the trans is shot.

superdave said:

I would say the pump in the trans is shot.

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I have thought of this too, however I have never heard of one goin out in a AW4 with 146k on it. Very possible though.

superdave said:

I would say the pump in the trans is shot.

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EZ to check. Remove the coil wire so it won't start. Take off the outflow tranny line. Crank it over. If it spews when your cranking, pump is OK. Installation is reverse of removal, trans. line, coil wire.

As far as the TC is concerned...climb under and see if the TC is in gear or if it popped into Neutral. If the TC is in N, it won't go anywhere, even if the tranny is in Drive.

In gear, in 2wd the lever on the TC will be straight up. Neutral would be two positions forward on the TC.

I shifted the trans case in and out of gear to no avail. All the linkage was in place and moving the selector and case arm. Could it be internal?

Ecomike said:

Hummor me here, check the vacuum line from the throttle body to the MAP sensor, see if it came loose during a backfire. It is common, and your description is a little vague, so lets start with an easy check.

If it can't get over 1500 rpm in park, there is sensor problem before the TC.

Click to expand...

Checked this and all is ok. MAP sensor vac line is nice and secure.

Pull the tcase. If it bench tests ok the the issue is in the trans.