Hey all.
I've had the problem for a while and now I've thrown it over the the dealership. This is the 2nd day they've had it now, and they still haqven't figured out the problem. I'm hoping somebody might have some info.

I've got a 99 runner with an Auto tranny.
When I drive it on the highway, or any highspeed where the OverDrive is engaged, and quickly take my foot off the gas, the truck shakes madly. It's only happening though when it's in 4th gear. The dealer told me (no joke), "well, it's either the engine, the tranny, or the diff..." WTF???? Of course it's one of those three you idget!!!! Shesh!! It can't be anything else!!!!

Anyways, I'm hoping that someone else may share a similar curse.. and may be able to shed some light on this, so I can advise the dealer where they might be able to look.

I personally think it's the torque converter that toast, but that's just me...

Any help would be greatly appreciated.

Thanks!!!

Kevin.

 

here is my advice... let them replace all the parts they want until its gone.... haha.... you may be able to get a new engine out of it, or a whole new tranny.....

 

I'm not sure with out looking at it but it might also be the Cat. If it is plugged and your engine isn't running properly you can have some back pressure going into your engine and causing that. I know it sounds strange but that is what was happening to my sisters cheap, oops I mean heap, sorry again, jeep, yeah thats it. Personally I hate cats, take a crowbar and knock your baffles out on it. At a minimum you'll atleast free up your exhaust air flow, can run cheaper (lower octane) gas and not worry about fouling your cat again if that is the problem.

p.s.
ever wonder why cats mysteriously have to run from one room to another? Their brain wave pattern matches that of a humans on acid (clinical research study @ the U.T. Health Science Center 1993).

 

First of all, that is a federal offense - I wouldnt go there, especially on this board. You will be in the minority and probably get flamed. Your low-end torque will go right down the crapper anyway.

Oakboy-

What's you mileage? I assume you are still under powertrain warranty right?

 

The cat converter would cause a shake only when it's in OD?? Hrmm an interesting theory. I've never thought of that myself.

I'm pretty sure though that' it's got to be the tranny. I noticed that it's not downshifting well, and it also slipped in first gear this morning...

I'm hoping that they'll replace the engine. Then when that doesn't fix the problem, and they replace the tranny, I'll have both things new !!!

Any other thoughts?

Thanks for the replies.

Kevin.

 

I've got 103,000 km's on her. Not too sure what that is in yankie miles haha

I've got ECP which is supposed to cover the powertrain and everything up to 140 K.

I was told when I first got this rig that the tranny and engines and practically bulletproof, so I'm a little suprised that I've got this problem.

 

Do you know the history on the vehicle? Maint and accidents included?

 

All I was able to gather was that the last owner was a woman. I wasn't able to pull the service records. The only warranty work done was the water pump. She bought it new and I'm assuming took care of it. I drained the fluids the first time myself, and the fluid looked pretty clear. Very little grit if any. There is an odd smell of gas in the engine oil though. I'm really hoping that my rings aren't gone. I've heard that the oil on this engine's got to be changed religiously. I'm hoping that she didn't push it beyond the service intervals...
I'll have to get that checked next.
I'm pretty suret hat she never had the tranny fluid changed, and I got mine changed a few thousand km's ago, but I don't think that would cause somethign like this. It's only when it's in 4th gear, and I take my foot quickly off the gas. I think though that it's slowly killing the rest of the tranny.

 

Make sure you don't have any snow. mud or ice buildup on the driveshaft or the inside of the wheels (take it for a carwash if there is any under there)......sounds stupid but it can throw things off and cause nasty vibrations.

What speed is this happening at?
If you hit the same speed without OD does it do it also?
Does it make it worse to accelerate? Deccelerate?

Need a few more hints to help you out.

 

Make sure you don't have any snow. mud or ice buildup on the driveshaft or the inside of the wheels (take it for a carwash if there is any under there)......sounds stupid but it can throw things off and cause nasty vibrations.

What speed is this happening at?
If you hit the same speed without OD does it do it also?
Does it make it worse to accelerate? Deccelerate?

Need a few more hints to help you out.

 

I spoke to the dealer last night, and they've decided to replace my rear differential. I noticed that there was some slack in the drive line when I was greasing the slip yoke. I'm assuming that they're going to try to correct that, however, I'm still wondering why the problem is only happening when I'm in 4th gear... I imagine that if there was a problem with the diff, I would be feeling that at all speeds.

I've fully cleaned the bottom of the truck from salt, mud, gravel etc. It's not so much a constant vibration mind you, rather it's a solid "thud" I can feel in my butt as well as I can hear that's coming after I take my foot off the gas.

Oh well. If the diff change fixes it, that's fantastic. I'm more than happy to get over 2000 worth of work on my truck for 50 bucks...

 

Let us know if that takes care of it.

 

Well, I had the new Diff put in , and I've driven it around for a couple days and guess what??? The problems still there!!

It's a little more faint now, but I think that it will get steadily worse like it did the first time. It's also happening at a higher RPM. It's about 2000 this time, and not 1500.

Also, they forgot to reset my parking brake after they pulled out the axels. I can pull the arm the entire way up now without engagin the rear brakes... gotta get em to look at that too...

I guess the next thing could be the tranny?? Any ideas?