Qx4 Offroad Problem

[tschweitzer]

Was on a really bad washed out mud road over the weekend. Got into some pretty deep mud and hit a pretty large hole going slow, but big enough to cause me to honk my horn on accident. Car performed great and had no issues until i got back out on to the highway. Now the car shakes pretty violently above 60 mph. No right to left, just vibrations. I'm assuming its just mud buildup in the wheels (happened to me once with my blazer). Tie rods and half shafts look fine, and there is mud in the wheels but not enough - in my opinion - to cause this much vibration. Any suggestions short of actually cleaning the car (which i can't do right now)? Used to drive smooth as silk, no vibrations at all. --2001 Qx4 4x4, brand new tires.

[tschweitzer]

Ok - Update, a good high pressure wash fixed the balancing problem, but unfortunately it uncovered another problem. When on the highway at high speeds, punching the throttle causes the car to almost waddle and shimmy for a second, almost like the the rear wheels aren't accelerating in unision. I've checked the obvious (broken shocks, brakes, etc). Could this be a malfuntioning Limited slip Diff, or drive shaft? No noises or vibrations associated.

[Issac]

Man the trailing arm bushings are weak on these trucks. I suspect that is what is up. There are many threads around on these lower arm bushings and the symptoms sound like it.

I just put on brand new arms from nissan, and they are so soft the move around a bunch even new.

I would get bushings from energy suspension, poly, personally. You would have to get universal bushings but just give measurements, which I will probably end up doing after seeing how pitiful the stock ones are.

The arms are $90 each and seem to get bad around 75 to 100k roughly. There is more info on this if you Search.

The front Differential carrier bushings are also pitiful which makes the front end wander under throttle and off in 4 wheel drive. These are another set of pitiful bushings. The center sits to one side of the bushing in a big way.

Personally I have played with these and feel that poly bushings, made to fit properly, are the way to go.

The pathfinder has real weak bushings everywhere. I suppose this is done for ride. Of course you have to buy the part and the brackets if you go to nissan, or you can replace the actual problem with the poly bushings.

Does take some tools and some skinned knuckles. But after you get it down, it is not bad.

The trailing arm bushing problem didn't stop with the 50 model.

[KoukiS14]

I concur -- probably the bushings.I had the same problem with the vehicle shaking violently after I spent a couple days stuck by the river as well. That was terrifying, but a good cleaning fixed that.

[tschweitzer]

Thanks guys - I've done a lot of research, looks like that's it. Cars at Nissan dealer now (no Infiniti dealer where I am) and they said everything looks fine. I'll have to go over there and actually take the mechanic for a drive. Worst case scenario, what am I looking at in terms of pricing? I trust this dealer, but I don't want to get screwed on pricing.

[tschweitzer]

Well, didn't end up taking the mechanic for a drive - should have though. He said everything was perfect looking under the car - even showed me. He said all the bushings were in spec. The car definately jags to the left when you step on the throttle or take your foot off the throttle above 60mph. I'll probably take it back later this week and take them for a drive. I'm more concerned with ruining my brand new michellins than anything else - don't want them to wear funny.

[Issac]

Well I am no pro mechanic, but I don't see how he could show you without taking them off. How could he tell from not loading it?

You can do this job yourself, save much money, and it is exactly 4 bolts to do it.

I would buy the stock nissan arms online, since they are the same.

Some serious safety precautions needed, and this is what makes the job not basic, and long wrenches 17 and 19 I believe because bolts can be really hard to remove. The rest is easy.

Might as well have them throw in new bolts for front and rear with nuts.They are different front and rear.

$200 I did it and feel more comfortable than a pimple faced teen doing it. Plus they look all nice for a few days.

Boy what a difference. They seem go out 75 to 100k so you can't go wrong by doing so. This funny feeling you are getting was named something like "pathfinder death wobble" in the old models and Nissan didn't solve it. The bushing is just way too soft. I can smash the new one out of center just by rocking my truck back and forth.

There are other options. Poly bushings, but this is work and not really hard but labor and hassle. Your choice.

I would say $400 total would be maybe a fair price. But I just cannot justify that when I could do it. Plus you will know where your fuel filter is under there and probably decide to do your differental fluid in the rear while you are staring at it.

It is what I would call an med/easy job. Harder than changing oil, maybe like doing a transmission pan/filter or something.

Oh there is an odd balance weight that is an outboard type metal wheel on a bushing that must do some vibration control. It sits on the rear bolts. I cleaned and put rust restorer on it and then stuck the bolt thru like it came out. Easy. Happy, and Drives straight!
Modified by Issac at 7:51 PM 3/17/2008