During the last couple of weeks, my '98 Grand Cherokee 5.9 has developed a driveline shudder. It has me puzzled.

It's sort of linked to speed, but not exactly engine speed. Meaning: it's more pronounced at some ground speeds, like 25-30 mph, and 70-75 mph, but it doesn't increase or decrease exactly with engine speed. It kind of increases when you hit the accelerator, but more with ground speed than engine speed.

My transmission has been leaking. About 5k miles ago I did a fluid/filter change. I torqued the pan bolts exactly to specs, but a couple times after that I found them loose enough to leak. So finally I put thread locker on them & torqued them down extra. The pan is dry now, but I just discovered I was down 2.5 quarts. Filling the tranny made no difference in the shudder. I've also replaced the viscous coupling in the transfer case, along with the chain several thousand miles ago. They've shown no symptoms & I see no sign of leaking there.

So I suppose I'm left with a wheel bearing going out? Or the driveshaft? Alignment? Bad tire? I haven't thrown any wheel weights. They all look in place. I'd think if it were a u-joint going out, the shudder would be getting worse, but it seems to have plateaued.

I also just replaced the spark plugs, plug wires, distributor cap, and rotor, thinking perhaps it was a misfire. Yep, the plugs were really worn: gap well over .060 … actually too large to measure with my gauge. But that didn't change the shudder either. I don't hear any scraping or squealing, like I might expect with a wheel bearing. And it feels more like a shudder than a vibration, if you get the difference. I don't see fluid on the bottom of the differential either.

Is this the torque converter going out? Is 2.5 quarts low bad enough to damage it? I wasn't doing any towing or heavy hauling. And i've seen trannies lower w/o damage. But I'm at 190k miles. I've only had it about 14 months & 10k miles, so my history with it is short.

If this really is a bad torque converter, what would "complete" failure look like? Will it just keep vibrating worse & worse until I can't stand it? Can it take out other components? Or is it possible that it will fail catastrophically & suddenly, either leaving me stranded, or with little bits & pieces that are more expense to fix later than sooner?

I look forward to your insights.

Thanks!

Thomas

 

Okay, I have 2 scenarios that I can relate to this. In my Chevy truck, the torque converter turbine blew up and it just stopped driving the truck at all. No warning, just bang and a sound like a jet airplane, then nothing. After taking apart the transmission, there were little pieces of metal all thru it, so a complete rebuild had to be done including the pump.

Right after buying my 97 ZJ, it started the shuttering any time there was a high load on the driveline. Too much throttle from a stop was in worst. Pulling up a hill before the downshift was also bad. Turns out the clutches in the tranny were toast and the seller had put some kind of additive in it to sell it and I was the lucky buyer. Of course he knew nothing! I should have known better because this guy was about to be deployed to Iraq and was selling it real cheap! By the time I was done with fixing it, I had $3500 invested in a POS 97! My only defense was it was my first jeep and it was love at first sight. He was the last of 3 soldiers who had owned it at Ft. Drum.

 

No! No! No! I want a different opinion!

But I'm not really surprised…

 

I have to agree with Dave, it sounds like the clutch is failing, and I would not be at all surprised if the sun gear was cracked...seen a few like that