Correct shocks please?

Pretty much everything on the bottom side of the coach: Steering, wheels, tires, brakes, suspension
Limier
Posts: 17
Joined: Thu Mar 12, 2020 2:46 am

Correct shocks please?

Post by Limier »

We have a 93 Serengeti Ivory, Torsilastic suspension, no airbags. 36’ Oshkosh Chassis No. 4CDN6BK23P2901854
The slightest bump in the road jars the front badly, and it porpoises as well.

Ride height measured up OK, so I’m guessing the shocks are worn and need replacing.
Current shocks are Koni, but age and model not known.
We’re in New Zealand so would prefer shock part no’s rather than a recommendation to a retailer I can’t buy from.

Thanks in advance
wolfe10
Posts: 222
Joined: Sun Oct 27, 2019 4:12 pm

Re: Correct shocks please?

Post by wolfe10 »

Before determining that the Koni shocks are bad, if they are the red/brown ones they are ADJUSTABLE.

What you are adjusting is dampening on extension where it controls bounce, but does not add to harshness on compression:

http://beamalarm.com/Documents/koni_reb ... edure.html
Brett and Dianne Wolfe
Ex: 2003 Alpine 38'. Ex 1997 Safari Sahara. Ex 1993 Foretravel U240
Moderator, FMCA Forums 2009-2020
Chairman, FMCA Technical Advisory Committee 2011- 2020
Moderator, http://www.dieselrvclub.org/ (FMCA chapter) 2002-
TDJohn
Posts: 552
Joined: Sun Oct 27, 2019 11:34 pm

Re: Correct shocks please?

Post by TDJohn »

Limier,

As Brett stated, check and see if your Koni shocks are the adjustable type. If they are, adjust them to maximum dampening. The shocks come from the factory set at least dampening, so odds are they were never adjusted, and might have life left in them. That said, also verify that the front shocks are the correct number as provided below. If you need, I can provide links to where you can purchase them, but those are US suppliers.

Also, have your coach weighed and then adjust your tire pressure according to the weight you are carrying per axle. If the tire is over inflated, it will give a very harsh ride and poor handling.

Here are the Koni part numbers you need:

Front: 88-1641SP3

Rear: 88-1458SP1

IMPORTANT: Be sure to order the shocks by part number, not by year, make, model of your coach, otherwise you will get the wrong, non effective shocks, and will have wasted your money.

Also, be sure to set all four shocks at maximum dampening (they come from the factory set at least dampening), especially if your drive on rough roads...

Another thing to note, I talked to Koni six years ago, when my Koni "Red" shocks arrived, painted black. The rep said that they come in a rainbow of colors, red, black, blue, safety yellow, etc. They are now Koni Reds in name only.
John
'95 Serengeti, Cummins C8.3-300
Allison 6spd.
Limier
Posts: 17
Joined: Thu Mar 12, 2020 2:46 am

Re: Correct shocks please?

Post by Limier »

Thank you both, John & Brett. I’ll try the adjustment first and see how it goes.
Regards

Bob Side

‘93 Serengeti. C8.3-250hp Cummins. 6 speed Allison. Oshkosh Chassis
New Zealand. Converted to drive on the left.
TDJohn
Posts: 552
Joined: Sun Oct 27, 2019 11:34 pm

Re: Correct shocks please?

Post by TDJohn »

Limier wrote: Sat Apr 25, 2020 3:23 am Thank you both, John & Brett. I’ll try the adjustment first and see how it goes.
If the shocks are adjustable, I would suggest to adjust the front and rear shocks to the maximum dampening, and see what it does.

What tires pressure are you running on the front tires???
John
'95 Serengeti, Cummins C8.3-300
Allison 6spd.
Limier
Posts: 17
Joined: Thu Mar 12, 2020 2:46 am

Re: Correct shocks please?

Post by Limier »

[/quote]

If the shocks are adjustable, I would suggest to adjust the front and rear shocks to the maximum dampening, and see what it does.

What tires pressure are you running on the front tires???
[/quote]

Currently they are 75psi, I’ve seen some info suggesting they should be 90psi but not sure if that’s correct.
TDJohn
Posts: 552
Joined: Sun Oct 27, 2019 11:34 pm

Re: Correct shocks please?

Post by TDJohn »

Limier wrote: Sat Apr 25, 2020 8:25 pm
If the shocks are adjustable, I would suggest to adjust the front and rear shocks to the maximum dampening, and see what it does.

What tires pressure are you running on the front tires???
[/quote]

Currently they are 75psi, I’ve seen some info suggesting they should be 90psi but not sure if that’s correct.
[/quote]

You need to have your coach weighed and than use your tire manufacturers tire inflation chart to set the proper inflation. Unless your coach is really weighed down, I doubt you need to go as high as 90 psi.

What tire size are you using?
John
'95 Serengeti, Cummins C8.3-300
Allison 6spd.
Limier
Posts: 17
Joined: Thu Mar 12, 2020 2:46 am

Re: Correct shocks please?

Post by Limier »

TDJohn wrote: Sat Apr 25, 2020 10:03 pm
You need to have your coach weighed and than use your tire manufacturers tire inflation chart to set the proper inflation. Unless your coach is really weighed down, I doubt you need to go as high as 90 psi.

What tire size are you using?
Tires are 9R22.5 all around
wolfe10
Posts: 222
Joined: Sun Oct 27, 2019 4:12 pm

Re: Correct shocks please?

Post by wolfe10 »

Post your axle weights and tire make/model if you like and we can verify PSI.
Brett and Dianne Wolfe
Ex: 2003 Alpine 38'. Ex 1997 Safari Sahara. Ex 1993 Foretravel U240
Moderator, FMCA Forums 2009-2020
Chairman, FMCA Technical Advisory Committee 2011- 2020
Moderator, http://www.dieselrvclub.org/ (FMCA chapter) 2002-
Limier
Posts: 17
Joined: Thu Mar 12, 2020 2:46 am

Re: Correct shocks please?

Post by Limier »

wolfe10 wrote: Sun Apr 26, 2020 7:16 am Post your axle weights and tire make/model if you like and we can verify PSI.
Unfortunately I can’t get actual axle weights until our lockdown ends. GVM is 22500lb. Tires are a mixture: Continental
Radial GS on the front, Toyo M120z & Giti GAL817 on the rear. (Not my choices, that’s what was there)

Thank you
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