Hey guys. 2005 Pathfinder SE 2x4 with 170k miles. I have replaced almost everything I can think of in the front end but am still getting bump steer, shimmies, and oscillation in the steering wheel. Here's a list of what's been replaced so far regarding suspension:

-Upper/Lower control arms (with ball joints and bushings)
-Tie rod ends
-Sway bar bushings
-Struts (Bilstein HD) and reused stock coils/mounts
-Tires (Balanced)
-Alignment (after every part replaced)
-U-joint

I'm stumped. The steering feels tight and the car drives straight on a smooth road. There is no vibration/oscillation on a smooth road whatsoever. However, the steering wheel shimmies violently over bumps and even turns by itself if I'm going 1mph over a speed bump or pulling into a driveway. When the freeway is slightly bumpy, the steering wheel oscillates slightly. It seems to do this under compression since going up a speed bump causes the steering wheel to turn and returns to straight once i'm passed the speed bump. I don't hear any knocks or noises at a low/moderate speed at all. Power steering fluid has been drained and replaced and there are no leaks from the boots. The alignment shop has a good reputation but have posted the numbers from a month ago just in case.

This has been going on for almost 3 years now and for the life of me cannot figure it out. I recall the steering problems happening overnight, as one day i drove the car and realized the steering wheel was shaking over bumps. After each part replaced, the car drove better but the problem has not been eliminated. Any help will be appreciated.

alignment data:

[/img]

Play in the rack and pinion?
Wheel bearings?

I think your right side TOE front and rear (especially rear) still need to come in more.

I know your readout shows them as in spec but....

I had the same issues as you though I have a 2008 LE 4X4 V8. I had my alignment done at a place that had really good reviews online. They have a Hunter Alignment machine.

My alignment TOE numbers after are - RF +0.07 RR +0.05. Left side numbers are the same as right side. Your Camber and Caster numbers look close to mine.

After the alignment our car handled the bumps much better. The issue of the steering wheel flying out of my hands when hitting certain types of bumps disappeared. However... the bump steer still exists although much less severe. Certain bumps are still felt in the steering wheel. Again not even close to as severe as it was before the alignment. Really I am almost getting used to it. Most bumps are just light blips in the wheel now if even felt at all. For the most part it rides really nice now. It is just some types of bumps or divots that I feel in the steering wheel. I no longer grab the wheel with both hands when approaching a small bump or uneven piece of road. The big bumps I still do.

I would recommend not going over 35 lbs on tire pressure if you are doing that.

I am convinced the bump steer is just part of the factory steering geometry. I don’t like it a bit but I don’t think there is any way to get rid of it all together.

I wish you the best of luck and suggest you ask your alignment shop to tweak it a little more.

Just an FYI...I too have terrible bump steer on my 2005 pathfinder. I also have the super soft rear springs and was getting complaints from pretty much everyone that sat in the back that the truck was SOOOOO bumpy. I don't tow but carry quite a bit of gear and people on occasion.

Anyway, I figured what the heck I'll try these Air Lift bags that everyone seems to use. I installed them Friday, inflated to 35 PSI as recommended in the instructions, took it for a spin and WOW! I dropped the pressure the next day to 18 PSI and let my wife take it up to the mountains.

All I can say is if my wife noticed a difference then it must work. She said the truck drove GREAT! I plan to get a good alignment as well just to see how it all shakes out but it was probably the most noticeable improvement I've ever made on a vehicle for 80 bux!

bubba59 wrote:Just an FYI...I too have terrible bump steer on my 2005 pathfinder. I also have the super soft rear springs and was getting complaints from pretty much everyone that sat in the back that the truck was SOOOOO bumpy. I don't tow but carry quite a bit of gear and people on occasion.

Anyway, I figured what the heck I'll try these Air Lift bags that everyone seems to use. I installed them Friday, inflated to 35 PSI as recommended in the instructions, took it for a spin and WOW! I dropped the pressure the next day to 18 PSI and let my wife take it up to the mountains.

All I can say is if my wife noticed a difference then it must work. She said the truck drove GREAT! I plan to get a good alignment as well just to see how it all shakes out but it was probably the most noticeable improvement I've ever made on a vehicle for 80 bux!

^ This. Air Lift bags cured the crazy "rear end bump steer" on my 2005. Even 0 psi capped keeps the stock springs from bottoming, I usually ran 10-12 psi.

But the Moog springs I just put in last week are the better option. They feel like 12 psi plus stock springs, but more linear through the travel (air springs ramp up after all).

Regarding "oscillation" noted by the OP - I too have been fighting this for a couple of years and finally got results I can post.
In the end it was about finding a good alignment shop.

My original alignment shop was great - actually Eric was great. He worked on my old QX4 after I ran it onto a boulder, and in 2013 he made my 2010 Pathfinder rock solid after I lifted it.

Several years ago I beat it up pretty good in the desert and went back to my shop, but Eric was gone.
The mechanic they put on my car acted like he didn't want to be there. He wasn't a perfectionist like Eric. He adjusted the toe and said everything else was "in spec". The car went straight, but it wasn't how it used to be. I started to notice an oscillation at freeway speeds.
Thinking it was old bushings, I replaced lower control arms, then the spring mount arms. I even tried to align it myself with mixed results.
Eventually I took it to a one-man shop who worked on 4x4s, and went on a desert trip the next day. I thought I was going to roll it on the freeway. Over 50 mph it rocked from side to side so badly, it was like a ship in a storm, whenever any small bump whatsoever was hit. My buddy wanted to get out of the car and run home. I pulled into a parking loot and pumped up the tires to 55 PSI to try and stabilize it but it didn't make much difference. I learned to countersteer and cancel the oscillation.

I don't believe in giving incompetent people 2nd chances to make things worse, so I made a serious attempt to do it myself again, using an alignment kit my friend bought. I found the front toe was over 1/4" (that's real bad) so I pulled it back to 1/16". Similar results in the rear.
The car was a lot better, but still not right. Anyway I got used to driving it this way for over a year. Countersteering became reflex. I made a video on the freeway at 60 mph, tug the wheel a bit and let go - it just rocked side to side forever. Speed up it would get worse, slow down it would stop.

Anyway I finally got a recommendation for Johnson's Alignment in Torrance just two miles from my house. Apparently this is where people take their track cars. There is a two week backlog and I finally got in yesterday, and yes there were lots of track and restored classic cars there. I was certain my steering rack or something was worn out.
They found my front toe was over 1/4" (so when I measured it at 1/4, was it really 1/2??) and he explained when there was more weight on one side the car would favor that tire then the weight would shift and favor the other tire, causing the oscillation.
Also the caster was wonky - one side was 3 1/2 degrees where it should be, but the other was 5 1/2 degrees. I have SPC upper control arms so they were able to get it in spec by moving the caster plate around.

So the conclusion is I jacked up the caster when 'froading, and two shops tried to make it go straight by tweaking the toe, instead of fixing the caster.

Find out where track guys in your region take their cars, and go there. I drove 80 today and it wasn't even scary!

And that's the sad truth, it's really hard to find good places that will work on your vehicle. It took me a good few years before I found a few local shops that I truly trust with my equipment. When it's something I can't conquer, I take it to them.
Glad you are once again happy with your ride!