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2019 E450 2350 Rough Ride

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RJW365

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Re: 2019 E450 2350 Rough Ride
« Reply #15 on: July 27, 2019, 04:32:35 pm »
This is a topic dear to my heart, yet I have a 2007 E350 chassis, hoping to soften our front suspension by soon replacing our stock E350 front coil springs with E150 coil springs.

To you with an E450 2350, as you have determined, your chassis is far over-rated for the actual load it is carrying.  The source of your jarring condition is related to an extra stiff, extra capable front and rear suspension.  What I share next is what I feel will get you going in the right direction, and it should be a very affordable solution compared to all other options. 

Keep in-mind that I am not an authority on all this.

During your next RV trip, fully loaded with a tank full of gasoline, propane, fresh water (no waste water), whatever you typically mount on your rear hitch, all your stuff including clothing, supplies, cookware, food, bottled water, and also you in your typical seating positions inside the RV.........get your rig weighed at a truck stop with a truck weigh scale.  Weigh each axle independently as is common practice on those scales.  With the weight numbers, you can determine the difference between your actual weight on each axle, and compare those numbers with the capability of each axle.  I am NO EXPERT HERE so don't take my word as gospel, but I feel you want your actual load per axle to be 500-750 pounds less than the axle's capability.  If the gap is significantly more, your ride will be quite rough as you are experiencing today.

I did that exercise with our 2350.  Our front axle is extremely light with an actual load (worst case scenario) of 3260 pounds and a capability of 4600 pounds, a 1140 pound difference.  On our heaviest trip ever, our rear axle weighed 8220 pounds on the rear axle that is capable of 7800 pounds, a deficiency (over-load condition) of 420 pounds.  Since then we are more mindful of what we carry and where we place the weight.

In your case with model 2350 on an E450 chassis, you won't have a rear axle over-load condition, but rather a severe under-load condition like I have with my front axle.  As I previously mentioned, I will soon swap my stock E350 4600 pound front coil springs with lower-rated ones designed for an E150.  I strongly advise to learn from my results before taking any such action with your own 2350s.

Regarding your rear suspension, a truck suspension shop should be able to take the weight numbers you provide and determine how many rear leaf springs to remove to decrease the amount of load margin to get you to the 500-750 number.

In my case, I wish I could add one more leaf spring per rear corner to increase my rear axle capability and lift it up to rid our slight rear end sag.  I can't add any leaf springs because the extra height will prevent the rig from clearing our already tight garage door clearance.

Thanks for the all the details and information.. a lot to digest and figure out our next move.  I will likely be calling PC and seeing what they can do to help or suggest.  BTW - is there a better way to reply to all the post replies?  it appears it is creating a new post each time I reply.  Everything is too damn time consuming :-)

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biglegmax

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Re: 2019 E450 2350 Rough Ride
« Reply #16 on: July 27, 2019, 06:26:38 pm »
We have a very similar, but different beast with the Quigley. They swap rims to 17" so our tires and pressures would be different.
 My thinking, and it might be flawed, if you are running max axle limits, run max air pressure, if not, drop your air pressure some. Its something that you have to feel comfortable with. We have a tire pressure monitor so I'm able to watch things pretty closely.

Personally I think you will be wasting your breath talking to PC. They have known about the 2350 sag for years and haven't addressed it. Quigley even put 3" spacers under the springs to help level out their work, but the house is designed with too much weight aft. It doesn't have to be that way.

I think we have both been sold a bill of goods with the air bags, I can't wait to get them off.

Doug

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biglegmax

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Re: 2019 E450 2350 Rough Ride
« Reply #17 on: July 27, 2019, 06:35:03 pm »
Ron:
Can you comment on the ride when you were over weight on the rear?
Doug

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CalCruiser

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Re: 2019 E450 2350 Rough Ride
« Reply #18 on: July 27, 2019, 07:19:58 pm »
80 psi is required  at or near an E rated tires load carrying limit. For example, my Bridgestone Duravis  R500 HDs are rated at 2680 lbs each at 80psi, meaning  maximum 5,360 lbs front axle / 10,720 lbs rear axle.
https://m.tirerack.com/tires/tiretech/techpage.jsp?techid=55

As Ron Dittmer demonstrated, a 2350 is several thousand pounds under those limits, so you should be ok running  the E350 2350  tire placard pressures. Mine are 65 front/60 rear.

Is this really a 2019 E350 2350 at Campers Inn ??
https://www.rvt.com/Phoenix-Cruiser-2350-2019-Selma-NC-ID8602809-UX198488
« Last Edit: July 28, 2019, 02:06:39 pm by CalCruiser »
Goin' where the wind goes...

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Ron Dittmer

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Re: 2019 E450 2350 Rough Ride
« Reply #19 on: July 27, 2019, 10:51:42 pm »
Ron:
Can you comment on the ride when you were over weight on the rear?
Doug
Having a rear axle over-load condition on our 2007 E350 2350 (with our lighter-weighted NO-slide-out floor plan), the ride in back is fairly smooth, yet still rougher than our family sedan.  I will always wonder if Koni-FSD shocks all around would help, but I likely will never find out because I am extremely happy with the Bilstein-HD shocks I recently installed.

I "test feel" the rear axle ride when Irene is driving on the open road, and I lay on my back on the floor with my head resting on the floor over the rear axle.  I feel the vibrations best that way.

Under our typical load conditions, the ride is a bit harsher than when over-loaded but not significantly so, because we always run very close to the 7800 pound rear axle load rating.

It is up front where I always felt our PC could benefit from a suspension adjustment, hence going to try E150 front coil springs.  I hope the results will provide a noticeably softer ride along with a little lower front stance, without a significant sacrifice to handling.  If the front end lowers enough for a greater clearance between my roof a/c to our garage door opening, then I will consider adding one more leaf spring in each rear corner to lift the tail a bit more.

Keep in-mind that our 2007 E350 2350, does not have the extra weight of a slide out which lightens the front axle, and our fresh water tank sits against the back wall which teeter-totters the weight even worse off the front and onto the rear axle.  Later model years  of the 2350 have the fresh water tank placed more forward and more centered side-to-side.  So my situation is worse than 2350 owners of a 2010 model year or newer.

About rear air bags.  I had them on our first motor home.  I had an on-board air compressor and controls by the driver so that while driving, I could add air or let out air pending the driving conditions.  More air in the air bags provided better handling which also made a rougher ride.  So I am surprised to read that people say to add more air in the rear air bag suspension to make a smoother softer ride.

Regarding the tire pressure.  That is one easy area where you can make a difference in the harshness of your ride, but you really need to know your weight per axle to know the right tire pressure.  All 4 rear tires get the same tire pressure.  The same up front, but they don't have to match the back.  Just 5 PSI pressure more than needed will yield a noticeably rougher ride.  For reference alone, I run 65 psi in all 6 of our tires, making sure my tire gauge is accurate.

« Last Edit: July 27, 2019, 10:54:23 pm by Ron Dittmer »
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Re: 2019 E450 2350 Rough Ride
« Reply #20 on: July 28, 2019, 05:24:56 pm »
It sounds as if I may be able to achieve a "softer" ride in my 2350/E-450 by running tires below maximum inflation.  Based on my weight ticket (attached) and load table here - https://www.goodyearrvtires.com/pdfs/rv_inflation.pdf -it seems I should easily be able to run fronts at 55-60# and rear dualies at 65#.  I'm wondering if anyone else is/has done this and what the results in ride comfort, handling and/or tire life were for you?

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RJW365

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Re: 2019 E450 2350 Rough Ride
« Reply #21 on: July 29, 2019, 10:20:05 am »
It sounds as if I may be able to achieve a "softer" ride in my 2350/E-450 by running tires below maximum inflation.  Based on my weight ticket (attached) and load table here - https://www.goodyearrvtires.com/pdfs/rv_inflation.pdf -it seems I should easily be able to run fronts at 55-60# and rear dualies at 65#.  I'm wondering if anyone else is/has done this and what the results in ride comfort, handling and/or tire life were for you?

Thanks everyone for your posts and comments.  I went to a CAT Scale yesterday and my 2019 E450 2350 has 3600LB in the front and 8720LB in the rear.  Total 12,320. (full water tank, empty gray and black)
So I guess I need to review the previous chart provided and determine the correct air pressure in front and rear vs going by the place card info? 
Also, it appears because I have to have 90LB in my rear heavy duty air bags to keep them off the inside block (per Bob at Elkhart Hitch).  The rear it not sagging and when you go over a long dip, you can tell the rear air bags are helping, so not convince they are contributing to the overall rough ride especially since most of the rough is experienced in the front.  Hard to say.  I plan to call Elkhart Hitch this morning and share the rear weight and see if he has any other comments related to the bags.


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CalCruiser

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Re: 2019 E450 2350 Rough Ride
« Reply #22 on: July 29, 2019, 12:13:21 pm »
That Goodyear chart  is  specific to size and make,  not generic.

According to this,  E450 2350s have LT225/75R16  tires, correct?
https://www.phoenixusarv.com/phoenix-cruiser-model-2350/

The tire placard located on my E350 door jam specifies LT225/75R16 @ 65 psi front / 60 psi rear.

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Ron Dittmer

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Re: 2019 E450 2350 Rough Ride
« Reply #23 on: July 29, 2019, 03:47:43 pm »
It sounds as if I may be able to achieve a "softer" ride in my 2350/E-450 by running tires below maximum inflation.  Based on my weight ticket (attached) and load table here - https://www.goodyearrvtires.com/pdfs/rv_inflation.pdf -it seems I should easily be able to run fronts at 55-60# and rear dualies at 65#.  I'm wondering if anyone else is/has done this and what the results in ride comfort, handling and/or tire life were for you?

Thanks everyone for your posts and comments.  I went to a CAT Scale yesterday and my 2019 E450 2350 has 3600LB in the front and 8720LB in the rear.  Total 12,320. (full water tank, empty gray and black)
So I guess I need to review the previous chart provided and determine the correct air pressure in front and rear vs going by the place card info? 
Also, it appears because I have to have 90LB in my rear heavy duty air bags to keep them off the inside block (per Bob at Elkhart Hitch).  The rear it not sagging and when you go over a long dip, you can tell the rear air bags are helping, so not convince they are contributing to the overall rough ride especially since most of the rough is experienced in the front.  Hard to say.  I plan to call Elkhart Hitch this morning and share the rear weight and see if he has any other comments related to the bags.
If you own model 2350 of any model year with or without a slide out, and you are putting in the maximum 80 PSI in your tires, that will surely give you a ride of torture to you and your house.  The only benefit to having so much air in the tires will be for improved fuel economy.

RJW365's axle weight numbers seems right to me.  Your front axle is roughly 350 pounds heavier than ours due to the placement of your fresh water tank and also that you have a slide out.  Adjusting your tire pressure to match your actual load will make a really big difference for the better.  Just BE SURE to use a trusted tire gauge.   If it is not a digital tire gauge, I would compare it to one.

90 PSI in those additional rear axle-mounted air bags sounds like a whole lot of extra PSI yielding a much rougher ride.  I recall with our previous motor home, the air bags of a different brand required a minimum of 15 PSI to prevent damage to them.  If you have an E450, I advise to research the minimum requirement for your rear air bags and set them to that minimum during a good long trip, and see what you learn from that PSI setting.  If you own an E350 with lower-rated rear springs and are leveling your rig with air bags, that is a different situation.

About the Phoenix supplied tire label in the door jamb.  For our 2007 PC 2350, the recommendation is real close to my actual load requirement.  I think most of my troubles in past years was related to bad tire gauges providing inaccurate readings by as much as 9 PSI.

It is interesting that the front axle load rating for the E350 and E450 are identical.  They have identical coil springs and all.  The difference in their load rating is all related to the rear axle.  So if you have a short PC with a light weight front axle, your E350 or E450 front suspension is going to make for a rough ride up front.  So MAKE SURE your front tires are not over-inflated.
« Last Edit: July 30, 2019, 08:03:20 am by Ron Dittmer »
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Re: 2019 E450 2350 Rough Ride
« Reply #24 on: July 29, 2019, 07:51:08 pm »
Hi Rob hope you get your new PC ride corrected.i know you will find a solution. 
BTW : I'm STEVE I PURCHASED YOUR PC 2100 you traded at the factory in Elkhart. We met there back in May . I want to say thank you  we love our 2100 you took excellent care of it . It's funny I was reading the the forum and I recognized your Doberman  picture and you being in Maryland  named Rob . Again we are super pleased with our 2100 PC  perfect for us . We been traveling quite a bit with it , rides nice with the Air lift ride you installed.

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Re: 2019 E450 2350 Rough Ride
« Reply #25 on: July 29, 2019, 08:02:06 pm »
It sounds as if I may be able to achieve a "softer" ride in my 2350/E-450 by running tires below maximum inflation.  Based on my weight ticket (attached) and load table here - https://www.goodyearrvtires.com/pdfs/rv_inflation.pdf -it seems I should easily be able to run fronts at 55-60# and rear dualies at 65#.  I'm wondering if anyone else is/has done this and what the results in ride comfort, handling and/or tire life were for you?
Thanks for the info.  Could you educate me on how to read the tire pressure charts?

Thanks

Ron S
« Last Edit: July 29, 2019, 08:06:29 pm by Sarz272000 »

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Re: 2019 E450 2350 Rough Ride
« Reply #26 on: July 29, 2019, 08:05:44 pm »
I am no expert on suspensions and could not recommend anything.  However, I know CoachHouse uses MORryde suspension.  The link below claims smoother ride. 

http://www.morryde.com/products/91-rs-suspension-system?return=%2Fproduct-category%2F4-suspension%3Ffilter%255B%255D%3Dall%26filter%255B%255D%3D10

It would be interesting to see if a former CoachHouse owner has any comments on the MORryde versus stock suspensions.

Ron S

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Re: 2019 E450 2350 Rough Ride
« Reply #27 on: July 30, 2019, 08:41:30 pm »
It sounds as if I may be able to achieve a "softer" ride in my 2350/E-450 by running tires below maximum inflation.  Based on my weight ticket (attached) and load table here - https://www.goodyearrvtires.com/pdfs/rv_inflation.pdf -it seems I should easily be able to run fronts at 55-60# and rear dualies at 65#.  I'm wondering if anyone else is/has done this and what the results in ride comfort, handling and/or tire life were for you?

Thanks everyone for your posts and comments.  I went to a CAT Scale yesterday and my 2019 E450 2350 has 3600LB in the front and 8720LB in the rear.  Total 12,320. (full water tank, empty gray and black)
So I guess I need to review the previous chart provided and determine the correct air pressure in front and rear vs going by the place card info? 
Also, it appears because I have to have 90LB in my rear heavy duty air bags to keep them off the inside block (per Bob at Elkhart Hitch).  The rear it not sagging and when you go over a long dip, you can tell the rear air bags are helping, so not convince they are contributing to the overall rough ride especially since most of the rough is experienced in the front.  Hard to say.  I plan to call Elkhart Hitch this morning and share the rear weight and see if he has any other comments related to the bags.
If you own model 2350 of any model year with or without a slide out, and you are putting in the maximum 80 PSI in your tires, that will surely give you a ride of torture to you and your house.  The only benefit to having so much air in the tires will be for improved fuel economy.

RJW365's axle weight numbers seems right to me.  Your front axle is roughly 350 pounds heavier than ours due to the placement of your fresh water tank and also that you have a slide out.  Adjusting your tire pressure to match your actual load will make a really big difference for the better.  Just BE SURE to use a trusted tire gauge.   If it is not a digital tire gauge, I would compare it to one.

90 PSI in those additional rear axle-mounted air bags sounds like a whole lot of extra PSI yielding a much rougher ride.  I recall with our previous motor home, the air bags of a different brand required a minimum of 15 PSI to prevent damage to them.  If you have an E450, I advise to research the minimum requirement for your rear air bags and set them to that minimum during a good long trip, and see what you learn from that PSI setting.  If you own an E350 with lower-rated rear springs and are leveling your rig with air bags, that is a different situation.

About the Phoenix supplied tire label in the door jamb.  For our 2007 PC 2350, the recommendation is real close to my actual load requirement.  I think most of my troubles in past years was related to bad tire gauges providing inaccurate readings by as much as 9 PSI.

It is interesting that the front axle load rating for the E350 and E450 are identical.  They have identical coil springs and all.  The difference in their load rating is all related to the rear axle.  So if you have a short PC with a light weight front axle, your E350 or E450 front suspension is going to make for a rough ride up front.  So MAKE SURE your front tires are not over-inflated.

Ron, thanks for the reply and details! Much appreciated.  The tires installed on the 2019 2350 E450 are Hankook. Tire size is LT225/75R16E.  I will definitely be reviewing the tire pressure ratings and  have always used Acutire digital gauges. The pressure rating on the PC card is 75 front and 80 rear which is what I have inflated but appears this is part of my problem.   The heavy duty version of the air bags on my E450 may also be attributing to the problem. My previous RV 2018 2100 had the standard air bags and keeping 30LB was perfect.  Since we jumped to E450 they wanted to use the heavy bag with a safety block in the bag to prevent tear.  If less than 90LB the damn block is hitting and not helping the rear ride.   I have an active conversation with Elkhart about the pressure ratings in those bags to support the vehicle rear weight.  My 2350 does have a slide out with fridge and couch.  Thanks again and I will update again when I have any new information.

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Re: 2019 E450 2350 Rough Ride
« Reply #28 on: July 30, 2019, 08:51:10 pm »
Hi Rob hope you get your new PC ride corrected.i know you will find a solution. 
BTW : I'm STEVE I PURCHASED YOUR PC 2100 you traded at the factory in Elkhart. We met there back in May . I want to say thank you  we love our 2100 you took excellent care of it . It's funny I was reading the the forum and I recognized your Doberman  picture and you being in Maryland  named Rob . Again we are super pleased with our 2100 PC  perfect for us . We been traveling quite a bit with it , rides nice with the Air lift ride you installed.

Steve, good to hear from you and hope all is well.  Glad you recognized our Doberman!  That is too funny.  We did enjoy that RV and features but really needed a little more room thus the next level upgrade.  We also had a couple issues but PC was very helpful with repairs.  I hope you continue to enjoy your new PC 2100.  Take care!  Safe Travels.

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Ron Dittmer

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Re: 2019 E450 2350 Rough Ride
« Reply #29 on: July 31, 2019, 08:01:13 am »
It sounds as if I may be able to achieve a "softer" ride in my 2350/E-450 by running tires below maximum inflation.  Based on my weight ticket (attached) and load table here - https://www.goodyearrvtires.com/pdfs/rv_inflation.pdf -it seems I should easily be able to run fronts at 55-60# and rear dualies at 65#.  I'm wondering if anyone else is/has done this and what the results in ride comfort, handling and/or tire life were for you?

Thanks everyone for your posts and comments.  I went to a CAT Scale yesterday and my 2019 E450 2350 has 3600LB in the front and 8720LB in the rear.  Total 12,320. (full water tank, empty gray and black)
So I guess I need to review the previous chart provided and determine the correct air pressure in front and rear vs going by the place card info? 
Also, it appears because I have to have 90LB in my rear heavy duty air bags to keep them off the inside block (per Bob at Elkhart Hitch).  The rear it not sagging and when you go over a long dip, you can tell the rear air bags are helping, so not convince they are contributing to the overall rough ride especially since most of the rough is experienced in the front.  Hard to say.  I plan to call Elkhart Hitch this morning and share the rear weight and see if he has any other comments related to the bags.
If you own model 2350 of any model year with or without a slide out, and you are putting in the maximum 80 PSI in your tires, that will surely give you a ride of torture to you and your house.  The only benefit to having so much air in the tires will be for improved fuel economy.

RJW365's axle weight numbers seems right to me.  Your front axle is roughly 350 pounds heavier than ours due to the placement of your fresh water tank and also that you have a slide out.  Adjusting your tire pressure to match your actual load will make a really big difference for the better.  Just BE SURE to use a trusted tire gauge.   If it is not a digital tire gauge, I would compare it to one.

90 PSI in those additional rear axle-mounted air bags sounds like a whole lot of extra PSI yielding a much rougher ride.  I recall with our previous motor home, the air bags of a different brand required a minimum of 15 PSI to prevent damage to them.  If you have an E450, I advise to research the minimum requirement for your rear air bags and set them to that minimum during a good long trip, and see what you learn from that PSI setting.  If you own an E350 with lower-rated rear springs and are leveling your rig with air bags, that is a different situation.

About the Phoenix supplied tire label in the door jamb.  For our 2007 PC 2350, the recommendation is real close to my actual load requirement.  I think most of my troubles in past years was related to bad tire gauges providing inaccurate readings by as much as 9 PSI.

It is interesting that the front axle load rating for the E350 and E450 are identical.  They have identical coil springs and all.  The difference in their load rating is all related to the rear axle.  So if you have a short PC with a light weight front axle, your E350 or E450 front suspension is going to make for a rough ride up front.  So MAKE SURE your front tires are not over-inflated.

Ron, thanks for the reply and details! Much appreciated.  The tires installed on the 2019 2350 E450 are Hankook. Tire size is LT225/75R16E.  I will definitely be reviewing the tire pressure ratings and  have always used Acutire digital gauges. The pressure rating on the PC card is 75 front and 80 rear which is what I have inflated but appears this is part of my problem.   The heavy duty version of the air bags on my E450 may also be attributing to the problem. My previous RV 2018 2100 had the standard air bags and keeping 30LB was perfect.  Since we jumped to E450 they wanted to use the heavy bag with a safety block in the bag to prevent tear.  If less than 90LB the damn block is hitting and not helping the rear ride.   I have an active conversation with Elkhart about the pressure ratings in those bags to support the vehicle rear weight.  My 2350 does have a slide out with fridge and couch.  Thanks again and I will update again when I have any new information.
Ah, I understand about your air bags.  You MUST add 90 PSI to prevent internal bottoming-out.  Good that you are working with Phoenix on it.  I understand why you had rear air bags on your previous 2100, an effort to lift the rear to level it along with improved handling.  Why did you add them on your E450 2350?  Did you think...."They helped before so they should help on my new rig?"  I would consider removing them.

About the Phoenix supplied tire pressure sticker.  The recommended 75 PSI in the front and 80 PSI in the rear sounds like a lot more air than your load requires.  Maybe they accidentally placed the wrong sticker.  Ask Phoenix about that.  Maybe they can sent you the right sticker.  Your numbers should be around 60-65 PSI.

Back to air bags.  Our old rig with air bags was proportioned similar to model 2100, a short rig with a large rear over-hang.  CLICK HERE TO SEE IT  The air bags with lots of air stabilized it and lifted it a few inches.  But the ride was rough with a lot of air.  So I adjusted more air or less air as the driving conditions required.  If you look at the picture taken through the driver's door, you can see the air bag control unit with air gauge, located by the driver's left knee.  One button turned on the air pump.  The other button let out air.  Another picture showing the battery compartment & converter, also shows the air compressor.
« Last Edit: July 31, 2019, 08:30:03 am by Ron Dittmer »
Ron (& Irene) Dittmer