mtyson

Hello fellow jeepers

I have a 1997 Cherokee sport 4.0 inline 6 4x4, I love it, but it came with all sorts of issues when I bought it about 2 years ago.

My current problem is what I will try to describe. It is a hard shift, I believe. It's a clunk that occurs intermittently. Most reliably, this occurs when going from a dead stop, you are accelerating smoothly, and then cuh-clunk as it shifts into 2nd.

Usually it shifts as smooth as you please, but this becoming more common. It is both a noise and a feeling.

My friend who is actually a mechanic has taken a look. He spent a long time feeling the drive shafts and u-joints, yokes etc. He said there is some slop where the rear pinion goes into the diff (my lack of knowledge is showing here), but overall doesn't seem like that could be it.

He said there is also play in the steering wheel and perhaps some bearing noise in the rear wheels, these were going to explore tomorrow. He says these are less likely the culprits, but let's eliminate them and the pinion...

And if those are not the issues then it is probably "inside the transmission" and probably means installing a new tranny.

Can anyone give us some more insight? I want to keep this baby on the road!

DFlintstone

Both of my AW-4"s, up shifting with a firm throttle can sort of "hit" when it shifts. Normal and no problem. If your exhaust was very near the floor or something it just might "bonk" what is near when the trany shifts, is all I've got.

BlueRidgeMark

That's the stock answer given by people for whom transmissions are a deep, dark, scary mystery.

It might be true. It's probably not.


Hows your fluid? Color? Smell? Level?

Mekgirl

I was having a similar issue sort of, at low speeds. It would act like it was bogging out. I replaced both the crank sensor (which causes weird idle and acceleration issues at low speeds) and the idle air control valve, and it seemed to fix the problem. A friend of mine told me it was the trans, but it didn't feel like it was slipping or grinding gears.
I'm assuming yours isn't showing codes?

mtyson

Thanks everyone!

1) trans fluid is good, I did a service/new filter about 1 year ago when I replaced solenoids
2) No codes

I'm going to look into crank sensor/idle air control valve.

Thanks for ideas!

Mine also does not seem to be grinding or slipping at all.

I just replaced the trans mount last week, and the exhaust doesn't seem to be hitting anything.

BTW: How much movement in back-end is normal when shifting? It moves quite a bit on mine, relative to the exhaust...

fb97xj1

Back end of what? The transmission, or the axle?

mtyson

Sorry, by back-end I mean the rear differential.

fb97xj1

Thought so, but wasnt sure. Is the diff trying to point upwards under acceleration? Thats axle wrap. Weak leaves will do that. The clunk could be the splines just needs greased.

DFlintstone

Shifting forward-reverse is where you might hear a clunk from worn ring/pinion, drive-line. Accelerating with constant torque, that shouldn't be an issue. Random dyeing or no start is what you might expect from a CPS.
Trouble with the IAC would normally show up at idle.

mtyson

OK, this is awesome info, thanks.

My buddy did say something about the leafs looking not great (can't remember what the exact issue was). I know they looked rusted as heck.

He also mentioned there were four u-bolts on the r. axle, but nothing on the differential itself, centered as it were. He said that might be by design, but there might be a missing support there?

When you mentioned acceleration, that reminded me the movement I saw on the diff was when brake depressed, and accellerating in both fwd and reverse, you would see the diff lift maybe 1.5 inches (total SWAG).

I'll research about the splines, I'm not sure what those are yet

thanks again guys.

fb97xj1

Look into this.

http://www.jeepforum.com/forum/f11/g...ite-up-357569/

DFlintstone

Maybe with a supper good light take a close look at where the U-bolts go around the axle and see if you can see any sign it's been slipping. For the nose of the diff to move much either it's slipping there or the springs are supper jacked up

My rear drive-line doesn't have a slip joint with a spline > https://en.wikipedia.org/wiki/Spline_(mechanical)

BlueRidgeMark

Nope. 2 U-bolts holding the spring to the axle on each side, for a total of 4 U-bolts. That's it.

There are also the two shocks to consider.

Sounds like your springs might be shot, and if they are, there's a good chance your shocks are gone, too. Lots of info on this site about replacing them (springs and shocks).

mtyson

Both of those links just blew my mind! I'll update when I get a chance to look at the jeep tomorrow. Followed the spline link to fly wheels... interesting...

Lubing the splines sounds very promising.

I just did the shocks, so should be ok there... what do I look for on the leaf springs exactly?

BlueRidgeMark

Arch.

Are they flat? Or do they have a negative arch? If either is true, they are shot.

They should have a noticeable positive arch.

A negative arch means the ends of the spring are lower than the mid point. A positive arch means the ends of the spring are higher than the midpoint.