Hard Ride in Precept

[dweber]

We have a 2019 Precept that literally jars the crap out of you. When driving you feel every crack and hole. It is terrible riding in this. We have Michelin tires all the way around. It has J- ride plus. Steering stabilizer etc. recently we were suggested to change our shocks to the Koni EV90 series. Suppose to be very best available
And they are very expensive. After putting $1500.00 worth of shocks on no difference.
Is anyone else experiencing this and how have you resolved.

[Grumpy]

Have you weighed it and adjusted tire pressure accordingly. May have the pressure too high. KONI's are the best and worked great on our 08 SENECA.

[dweber]

Have messed with air pressure up and down

[Grumpy]

Originally Posted by dweber

Have messed with air pressure up and down

You said KONI 90 their spec says 8805, is that what you installed? If not you may have the wrong shock.

[jubalr]

We have the 2018 Precept 36T. I put Timbrens on all 4 corners and Evo shocks in the front. But the biggest difference for the jarring of holes and bridge transitions was tire air pressure. I'm running 85 front and 90 rear.

[craigav]

Just out of curiosity I did a check on Youtube and found from Henderson's (well known for RV suspension upgrades and alignments) that the F53's as they got heavier with newer F53 models that they tested a dual 8805 configuration that many reported was too firm and then Koni made a 90 series for the F53's. There are not many comments in the video however I would suggest to read them as well.

My thought, it is very hard to have any shock provide the smoothest ride and the best handling as both concepts (when it comes to shocks) are for the most part opposite of each other. Too soft then handling suffers especially in curves, too firm then handling is much better but the ride is more harsh.

https://www.youtube.com/watch?v=LqBmxuz3nG8

[Grumpy]

Originally Posted by craigav

My thought, it is very hard to have any shock provide the smoothest ride and the best handling as both concepts (when it comes to shocks) are for the most part opposite of each other. Too soft then handling suffers especially in curves, too firm then handling is much better but the ride is more harsh.

But that is what supposedly makes KONI different with their FSD valving. They are also one of the world leaders in shock technology. As I've mentioned before they made a huge difference with our 08 SENECA. If I remember correctly, the ones that the shop installed for me were adjustable.

Henderson Line-up in Oregon, who is supposedly the best shop around when it comes to RV suspension, highly recommends them.

[craigav]

Originally Posted by Grumpy

But that is what supposedly makes KONI different with their FSD valving. They are also one of the world leaders in shock technology. As I've mentioned before they made a huge difference with our 08 SENECA. If I remember correctly, the ones that the shop installed for me were adjustable.

Henderson Line-up in Oregon, who is supposedly the best shop around when it comes to RV suspension, highly recommends them.

Koni FSD isn't really all that different than many other shocks, not that all Shocks are FSD, but other companies such as Bilstein have a similar technology such as Bilstein's Comfitrac® and Bilstein digressive valving shocks and I think Monroe Matics (if they still make them) are all similar (and there are likely others as well) in that the valving tightens the shocks to become more firm under a faster change than a slower change in the shock piston's movement. The issue is that even selective dampening is still limited to what they can do but overall I believe that they are better than non-selective dampening shocks. My bet is the 80 series has a range that is less firm at both the high and low end (frequency as Koni calls it) and the 90 series starts off firmer and can get even more firm than the 80 series. ~CA

[Grumpy]

Originally Posted by craigav

My bet is the 80 series has a range that is less firm at both the high and low end (frequency as Koni calls it) and the 90 series starts off firmer and can get even more firm than the 80 series. ~CA

If that's the case then he may have the wrong shock. KONI shows the 8805 for the F-53 chassis up thru 2024.

Recommended for TIFFIN rigs too.

Koni FSD Motorhome Shocks 8805 1019 for the Ford F53/Tiffin Allegro Chassis are a top choice for motorhome and RV owners seeking to significantly improve ride comfort and handling. The Koni state of the art FSD technology (Frequency Selective Damping) has become a game changer for RV owners worldwide. Features of the Koni FSD 8805 1019 Frequency Selective Damping Technology (FSD) The Koni FSD technology allows the shocks to automatically adjust damping based on road conditions.

[Kevin Cooper]

Originally Posted by dweber

Have messed with air pressure up and down

What pressure was the lowest, and what pressure does the sticker in the motorhome say?

[craigav]

Originally Posted by Grumpy

If that's the case then he may have the wrong shock. KONI shows the 8805 for the F-53 chassis up thru 2024.

Recommended for TIFFIN rigs too.

Koni FSD Motorhome Shocks 8805 1019 for the Ford F53/Tiffin Allegro Chassis are a top choice for motorhome and RV owners seeking to significantly improve ride comfort and handling. The Koni state of the art FSD technology (Frequency Selective Damping) has become a game changer for RV owners worldwide. Features of the Koni FSD 8805 1019 Frequency Selective Damping Technology (FSD) The Koni FSD technology allows the shocks to automatically adjust damping based on road conditions.

The word "wrong" is a bit subjective. Based on the video I shared and with other vehicles I have owned(I never owned an F53) there is generally multiple choices in shocks for a vehicle even with shocks from the same manufacture. I have known many people that believe(d) that the most expensive shocks would provide the best ride overall however many find that they are mistaken. The best ride is also subjective as often the OEM shocks provide the smoothest ride on a smooth road but they lack in a firm handling of the vehicle on a rough road or when making quick turns for example, an upgrade to oem shocks (especially those with variable valving) can certainly provide for a firmer ride with increased handling abilities and yet not be too firm on smooth roads as long as it is not too firm to begin with. The top end shock is often not the shock that gives the smoothest ride but generally speaking it provides for the most dampening effect (more firmness), which makes for a less smooth ride on a smooth road but it enhances the handling quite a bit.

The 90 series shocks are also correct for the F53 and from what I gather from the video, those F53 owners who wanted to upgrade their oem shocks often would choose the 80 series which is a good choice for many (perhaps most), those who still wanted even a more firm ride than the 80 series and in the case for perhaps a heavier F53 have installed a kit that allowed for 4x 80 series shocks per axle (prior to the 90 series availability), and these RV'rs in many cases stated that was too firm of a ride and therefore the 90 series came out for the F53's which are firmer than the 80 series are but not as firm as doubling up on the 80 series.

In any case, I agree with you that the 90 series may certainly be the wrong choice in this case and I suspect that they certainly could be too firm for many RV'rs preferences, not that they are wrong though in the fitting and availability for an F53. I would say it is more like oem equals the softest ride, 80 series are soft enough in most cases, but overall they are a bit more firm than oem, and the 90 series being the most firm and a step up in firmness over the 80 series.

https://supersteerparts.com/products...0nf45Hxh4E8zAU

[Sredbeard]

My 2020 precept handled terrible and rode just as bad. Threw over 1000 dollars at it and made minimal difference. Was not fun to be on road unless no tractor trailers and a new paved road which have fun finding. Had liquidsprings installed and a TOTAL difference. Yes it was expensive but in my opinion was worth every penny

[BrianMaryC]

I put Sumos on the front after the first several trips in our 2019 26X. We were happier after that. It really cushioned the small/medium bumps well and alleviated some pain of very bad roads.
I had already put a steering stabilizer on, adjusted air down near to what the RV specified (not the max cold pressure that the dealer had it at) and had it aligned.
Then at about 30,000 miles we replaced the original front tires because I found there was a big chunk of tread missing in one. Recently, I had the front shocks replaced with the Monroe RV shocks which smoothed it more.
I also removed the dash, sealed it up at the firewall and insulated. That eliminated the dash banging, air infiltration and some engine/road noise. The road has to be pretty bad for us to be jarred in our seats.
We can easily hear each other talking which occasionally gets me in trouble...

[RoyB]

We also switched to liquid springs two years ago. It is very expensive but gives a ride that compares with a luxury pickup. I purchased a set of front and rear Sumos for our 2019 Precept a couple of months before deciding to go with LS. They are still sitting in their shipping boxes and have never been used. I would be willing to send them to you if you're interested.

[embeleco]

Originally Posted by RoyB

We also switched to liquid springs two years ago. It is very expensive but gives a ride that compares with a luxury pickup. I purchased a set of front and rear Sumos for our 2019 Precept a couple of months before deciding to go with LS. They are still sitting in their shipping boxes and have never been used. I would be willing to send them to you if you're interested.

Hey Roy. Will those Sumos work for a 2022 Jayco Alante 27A? GVWR = 18k. I was planning to do only the Front Sumos on my rig.

[cherv]

our 2019 Jayco also rides like a brick. change to koni shocks in read , replaced sway bars front and rear, steering stabilizer from Roadmaster. some what better ride with tire pressure in rear at 80 psi and 75 psi in front.. lowered psi to 75/70 no big difference. started to run with full fresh water tank, made ride better due to added load on rear springs. no loss of mpg at around 9.0. maybe your rear springs/helper springs are out adjustment left to right.. that is my next check.

[BeachRock2020]

It’s a house on a truck frame. I wish I could afford nice class A diesel with air suspension, but I have a budget. The Jayco Jride Plus will just have to do.

It’s one of those questions, is the cup half full or is the cup half empty?

[Alante31V]

Might help but have not tried, putting actual weights in front compartments (ones in front of entry door if you have them) to put a load on the front springs to help compress/dampen. That is, if you are not already maxed out the front GVWR. I place all the heavy items we take, ie toolbox, in front. We also flat tow an Equinox. With 1/3 water, it does struggle on trips with high elevation climbs. 3,000-6,000 above sea level, Smokies, West Virginia or Yellowstone area.

Anyway, steel plates/gym barbell weights, bricks or concrete blocks will work too. Start with 150lbs each side. Some posters used cases of water bottle packs.

Our 2021 Alante 31V V8 18K chassis is hard, even with Koni’s/Sumos all around. But ‘lil better with vs without (stock).

[TGoldsbury]

Definitely need to check that you have the right tire pressures. I have a 2018 31UL with Michelins. Talked to the Michelin tire technical rep, he said to weight all four corners separately and call him back. After I did that he said to put 90psi in the front, and 70psi in the back. That definitely helped. As far as getting it weighed, our local landfill weighed it for free. Also could use a truck stop. But make sure to weigh all four corners separately, my driver and passenger sides were pretty even, that's why the pressures were the same. Depending on how you have your coach loaded may change you pressures.