cold suspension question

[carl]

I 've had an irratating front end knock on the drivers side for awhile when driving over small bumps only. I have replaced everything in the strut ass'y and it hadn't gone, but now since the weather has gotten cold (down to 32 degrees F) the knock has vanished and the suspension feels tight...and right. Actually the front suspension always feels bad in the warm weather--hard vibration like riding in a train when going over normal road bumps, but then all that vanishes when it gets cold out and it feels right.

As soon as the warm weather arrives so will the noise and that slop sound. Is this more likely noticable due to the tires 'giving' less in the cold weather? All the front end links feel tight. I've tried cold spray on some of the bushings in the past but couldn't locate it (maybe because the cold spray dissapates so fast in the warmer weather??)
Any ideas apprecated.

[OH2LS]

Is the vibration occurring under load, or just when your cruising? This is an interesting issue. Have you checked your intermediate steering shaft? Sometimes it requires a re-lube.

[wjcollier07]

Yeah, it's probably your ISS. The truck does the same thing...when it's above 70 degrees out, it'll knock horribly over small bumps..worse when its really warm, and when it's cold, just about anything below 70, more like 60, it won't do it at all. Guess the grease needs to be thick.

The dealer has a grease kit for the ISS...you could look into that if you're feeling confident, otherwise, have it replaced..I believe there's a newer version out.

[carl]

Hi sorry for the delay getting back on this. It is cold so its not an issue now.

Yes, the smaller the bump/slower the speed, the more the knock. In IL the roads are crap because the salt in the winter and the state that does nothing to correct it, anyway it really works the suspension. I hit a pothole last month that busted an upper front strut mount for 3rd time.

I will get back to this issue again when it warms and I will check the ISS. I have done nothing with that so far, I think guys are probably on it. Thanks for the help.

[00Beast]

In IL the roads are crap because the salt in the winter and the state that does nothing to correct it,

Um, the state applies the salt to the road to melt the ice. Salt is not a natural part of winter, it's so there isn't glare ice on the roads.

[Archon]

When you get around to the ISS, this is the procedure for it. Also, some after-market strut mounts can be noisy.
http://www.pontiacbonnevilleclub.com/fo ... f=55&t=217

[carl]

Thanks for the procedure. I will get back to this in the spring.

And yeah thanks for the salt insight, *dang* first no Santa Claus now this! What is winter coming to???

Where I'm from its a given about the state (as in government) being the source of many problems including the salt>>> the pot holes>>>the broken rusty cars, along with high property taxes, crooked politicians, and above all else doing little to correct the problems they cause. And they have no problem removing more of our wallet to do less. Other states do have better methods to deal with ice.

[00Beast]

Well, it's either salt the roads, or end up in a ditch. In Oregon and Washinton state I guess they use chemical ice melt, not salt. Most of the lower 48 that has winter snow and ice uses salt. It's a reliable method of melting the ice, at the expense of ruining cars.

[carl]

They have a sand/pebble/chemical mixture thats better, I think Indiana was using it for awhile. But still thats all about politics. Half the time when they need plowing trucks around here they are no where to be found, but then when they are not needed they are out tearing up the pavement. The real kicker is they did nothing significant to repair the roads after last winter and the taxes at an all time high. The last pot hole I hit @ 65mph, switching lanes on an expressway, felt like it almost removed my front tire. Well enough moaning, moving is the only solution.

[carl]

I read through Archon's ISS procedure again and had a few questions.
I have not replaced this ever before, but it appears easy enough. I have heard of some who claim that after replacing with the upgraded ISS the problem still returns in several months.

I just checked the part at Rock and they have an aftermarket Dorman for 83$.
I don't know what was done by GM to make an improvements to the original or which grease they use, but might it be better idea just to keep the original and pack it with the super-viscous lube instead? The procedure suggests cv/wheel bearing grease.

[Archon]

GM changed from a splined shaft, to a double-D design and made some changes to how the upper U-joint is attached. If you look at the picture at RockAuto, and compare that with the one in the procedure, you can see that difference.

FWIW, I have not had to re-grease the shaft since writing that. Which one you decide to do depends on how much you want to spend.

[carl]

Ok got it. I called Rock checking for a Delco replacement and they said not available, and also that Dorman part is on national backorder anyway, (probably while they update their old design).

The local GM dealer wants $165 for the latest design. RMS Parts offers the factory GM part at a discounted price of $125 plus about $10 shipping and 5-10day wait to get it from GM.

Anyhow thanks for all the info. Archon and esp. for your procedure.

[carl]

Updated ISS at GM direct right now is at $97 plus $20 s/h (out of stock), if anyone else interested.

[wjcollier07]

Got any part numbers to post? Always good to have floating around to make things smoother.

[carl]

Yep sorry, it was 26068295. Its in Archon's procedure link a few posts back in this thread.

[Archon]

You may want to grease the shaft in the meantime to see if that solves your problem. If not, then checking tie-rod ends, and ball joints would be a good idea.

[carl]

I checked everything seems tight.
The noise now is really bumping since it got warm. Its the ISS, I hear the same when I twist the steering wheel fast also. I will wait for the backorder to fill. Archon, when it arrives, would you suggest I re-pack the new design with heavier grease for a better layer cushion, or just leave it alone? Thanks again.

[Archon]

As I haven't seen the newer shaft, I'd suggest inspecting the grease that is on the shaft when you get it. If it is whitish, and thin, then if it were me, I'd use the heavier grease, as the thin stuff just doesn't seem to hold up.

[carl]

Ok, I just went through Archon's procedure . It took just over 3.5 hrs. I unknowingly created an access problem because I had the front end elevated slightly, as I was also working on the springs. I haven't driven it yet as I am still on stands working on something else at the moment.

Anyhow, I had to do a few things different on the ISS procedure, here they are:

1. I sliced the black boot under the dash completely, it makes it so much easier to access things. I sliced it, removed it, and zip-tied it back on when finished. The hardest part of doing this job is fighting those stiff frickin boots. The clear boot under the hood is wire re-inforced, its a real bear.

2. The procedure mentions turning the steering wheel 1/4 turn cw to access the ISS mount nut under the dash. I turned the steering wheel until I visually had best access to the nut. In my case it was 1/2 turn ccw.

3. I had to pull out the clear boot under the hood completely with the old ISS.. The clear boot used on my vehicle is tapered down at the end, and the bushing on the ISS is too big to fit through the wire re-inforcements on the boot when trying to pull the ISS out through it. So when your pulling to remove the old ISS... out pops the clear boot with it . Also getting the clear boot back in with the new ISS shoved inside is not the easiest of tasks.

4. The biggest time eater I ran into on this was trying to get the new ISS on the power steering shaft. The problem was that I fully compressed the new ISS assembly when I re-intalled it. This is beyond normal travel and it binds the u-joint making it impossible to get a good angle for the ISS to slide over the steering shaft. I had to extend the ISS shaft slightly when re-installing to free the u-joint, otherwise the u-joints range of motion is limited. I verified this was also the case with the old one that I removed.

And thanks again Archon for your procedure, all-in-all it went smooth. I'll let you know if this solves my clunk issue when I'm back in motion.

[CorbinDallas]

If you looking for the cheap way out, the origs pop up on fleabay under different part numbers, but most supercede to 26068295

Got a new one from a Deville
Asking $75 I bid $50 with free ship and got it