Bilstein or Koni?

[billybob]

My 1993 M-3430 Ivory has a very bothersome vibration in the front wheels. It feels like one or both of the front wheels are bouncing up and down. This happened with new tires for which I paid for a balancing job. It has a VC-22 Oshkosh chassis with leaf springs. One of those new tires could have a problem or the shop didn't balance them well but my bet is on the very old bilstein shocks. The number on the old shocks is 3191726W00. The recommended tire pressure is 80 psi all around which is what I run.

I've looked up shocks for it and consistently the recommended front shock is the Bilstein BSN-24-186414. I've also seen recommendations for Koni instead of Bilstein.

Any thoughts? Cross reference to a Koni part number?

[wolfe10]

Have you checked tire tires for RUN-OUT?

No shock will cure an "egg-shaped" tire.

[TDJohn]

I agree with Brett, but to answer your question, if you have worn out shocks, or will need shocks in the future, the Koni shocks will give you a smoother ride.

The Bilstien number you gave crosses to Koni 88-1641SP3

If you do decide to go with this shock, for your application, I would suggest setting the front shocks to maximum dampening and the rear at least dampening or about in between, medium setting.

https://www.ultrarvproducts.com/Koni-88 ... pine-Front

[billybob]

Thanks Wolfe10, I haven't checked the runout but great suggestion. I'll try that.

Thanks TDJohn. The Koni shock is only about $25 more per side.

[Mftag]

Along the same line of which shock, I would love it if someone on the forumn has the same chassis as mine and could tell me a model number for koni’s. I have a 2003 Safari, Zanzibar, 3512 SD, MID ENTRY. The issue is it has a Roadmaster D M4R chassis. There aren’t many of those chassis out there I’ve been told, Source Engineering can’t help and three sites have given me different numbers an some sites say it doesn’t exist. So if anyone has this chassis and can give numbers on front and rear koni’s I would really appreciate it.

Keep the shiny side up,
Mike & Colette w.Midnight the attack rabbit
2003 Zanzibar, ISL 370

[keegan8]

95 Sahara, 5.9, 6 speed, New Toyo tires, 9R22.5, 90 Rear, 85 Front, New Konis 88-1641SP3 like everyone suggest. Asked the shop to set to frim, rides somewhat smoother, but I'm getting a lot of bounce on small bumps and ruts. Doesn't just bounce once. Full water tank,

Is the firmness too much?

[wolfe10]

Is the firmness too much?

In a word, NO. The adjustable Konis have very little dampening on compression (where it would add to effective spring rate/make ride rougher).

The vast majority of their dampening, particularly when set on firm setting is on extension where it doesn't add to ride harshness but does a good job of dampening motion.

Are you sure the tech DID set the shocks to max-- very easy to do if you know to do it. Sadly, many techs do NOT know how. Instructions are on the KoniNA website:https://www.koni.com/en-US/Cars/Technol ... nt-Guides/

Were it me, I would remove the shocks, particularly fronts and VERIFY that they are set to firm.

[TDJohn]

Is your bounce coming from the front or back?
Did you change the rear shocks also? If yes, what part number did you use for the rear shocks? If you did replace all four shocks, it is possible that the mechanic mixed up the numbers and put the rear on the front and front on the rear. Mechanically, the shocks are interchangeable, meaning they will fit front or back, but there is a big difference in dampening rate and valving between the front and rear shocks. So if all four were replaced, part numbers need to be verified front and rear.

I agree with Brett. You will need to have the shocks removed and double check the setting. They come from the factory with least dampening, your coach needs the shocks set at max dampening, as Brett stated. From what you are describing, it is very likely that those shocks did not get adjusted, or as I stated above, it is possible that the shocks got installed wrong (front to back).

Also, if you have not done so already, be sure to weigh your coach fully loaded for travel, including full tanks (fuel, water, etc.). Being that you are using the 9R22.5 tires, I would not be surprised if you are maxing out the capacity of your front tires. Being that the this tire size is getting outdated/hard to find, in the future, when these tires age out, you might want to consider tire size 265/75R22.5. This size is the same diameter, but a bit wider, and the tire has a much higher weight capacity, allowing you to run lower tires pressure, resulting in a smoother ride and better handling. I have been running that size for a little over 9 years now, w/o any issues.

Let us know how you make out.

[keegan8]

Well, when I picked it up he didn't have them set to firm, he changed it, he know's what he is doing, the message didn't get to him about adjusting them. I sent the shocks directly to the shop, which is more than an hour away. French's Rv Repair in Camp Verde, decent guys to work with.

And I looked at the installation... this what I ordered.

shocks.PNG (149.92 KiB) Viewed 19909 times

So, according to all the posts, this should by right and that's how they got installed, red in the front.

Since the post, the bigger problem was that I discovered that it did have the Safety T Plus Blue stabilizer, but it was very old and was scraping the side of itself. And my steering was all over the place. My neighbor helped me removed it, and we couldn't push it down or retract it. It ten times better now with out. Go figure.

I think it's shot, Should I replace that damn thing, and will help further help?

[TDJohn]

Last time I spoke with Koni, they said that the shocks now can come in any color. I have received red, orangeish yellow, and black. In the older days, they use to be colored, but in the last 10 years it is a free for all, pretty much what ever color paint they can get the best price on. So I strongly suggest to crawl under the coach and verify by part number that they were installed correctly front to back.

As for the Safe T Plus, If nothing else is damaged besides the shock/steering stabilizer, then I would suggest replacing the shock/stabilizer. It will be very helpful and effective in case of a front tire blowout and it will likely also improve your overall steering and driveability.