FordE450 +jayco

jncrowe12 · February 18, 2016

I have a jayco motorhome on a Ford E450 chassis, original. Tires Michelin 225/75 with load factor E. max load of the tires is 9880lbs, my actual rear axle weight 9270 (static and motorhome empty with no water, fuel tank 1/3 full) according to Michelin that is asking for tire failure ( had 2 already) because the dynamic loads (going down the street, bumps - uphill - downhill- sideloads) will be over the tire limit. That's the reason the law requires pass, cars and light trucks to have a 16% reserve capacity; mine is down to about 2%. with full fuel and water tank, little bit of staff loaded for vacation or putting anything on the trailer hitch (boat or even loaded bike rack) I am overweight for the existing tires and max rear axle weight I know that is not an issue Ford has to deal but jayco.but I would very much appreciate your expertise about what to do (is that motorhome a risk to drive, maybe unsafe?) is there any means to increase the max rear axle weight on that E450 chassis? any way I could put on a different tire size (enough room on the rim / wheel-well;that would increase the max tire load about 1000lbs - but is that legal and doable, especially. With the dual tires. I am looking forward to your answer. I have doubts to buy new ford or maybe change the motorhome, haven't decided yet.

chirakawa · February 18, 2016

Are you wanting to tow a travel trailer with your motorhome?

Kirk W · February 18, 2016

original. Tires Michelin 225/75 with load factor E. max load of the tires is 9880lbs

Welcome to the Escapee forums! We will do all we can to help and assist you.

I did some digging and think that I have found the weight table from Michelin for your tires, assuming that you have XPS-RIB, LT225/75R16 E tires. You are quoting the rating for 4 tires when in dual configuration, or the total for the rear axle.........

Is the rear axle weight you list one from a scale where you had it weighed? Doing the math you would have only 610# capacity on the rear axle, which is very small for an RV. It does sound like Jayco should have used a higher rated chassis and tires for your RV. Axle ratings are based upon design parameters which include things like brake capacities, suspension parts, and a lot of things that are difficult to change. Those ratings are not an issue of law so much as one of warranty and such and you would need to talk with the Ford engineering department to know what can be done to improve weight capacity safely and not violate the warranty, assuming that the Jayco is still under warranty. It probably would improve your situation to go to a higher rated tire as long as you have the space in the wheel wells and you want to be sure that your wheels are rated for the larger tires and higher inflation pressures. A good tire shop can probably advise you on this, but be careful in where you get advice.

It isn't likely to be a legal issue but it may impact the reliability of the chassis from the added load on the axle, differential, transmission and even the suspension. I'm not mechanic enough to give very good advice in beefing up safely, but perhaps someone here may be. I really think that you probably would be wiser to sell this RV and upgrade if the financial side of things allows it. If you do so, make sure that you check the weight ratings of everything before you buy and get all of the information in writing as a part of the sale contract. Sadly, weight issues have been around for years and some RV manufacturers continue to ignore reasonable capacities and limits.

skp51443 · February 18, 2016

You can switch to heavier rated tires if you can find some that will fit, you might need new wheels for either any additional width or for a required pressure increase.

Not anything you can do to improve the axle rating aside from swapping axles.

The springs could be replaced with heavier ones that would give the chassis a bit of a lift. With duals there I'm not sure what you could find in the way of air-bag lifts that would fit.

Before you start spending money get each corner weighed, you need the individual wheel weights to see where you really are, axle weights can mask a situation where you have one wheel light and the other heavy. Escapees offers some weighing services that are very good and could also offer some suggestions based on their weights and your rig. You can also get the wheel weights yourself if you can find a scale that is in a level area and that you can roll one tire at a time onto.

LindaH · February 18, 2016

I'm curious as to why the OP's links in both this thread and the other one he started point to Palmetto RV?

skp51443 · February 18, 2016

Maybe trying to link to this page for a Jayco F-450 rig?

http://www.palmettorv.com/used-rv-jayco-greyhawk-31ss-9800-miles-mt-pleasant_vid_5539189.html

Not sure about the other topic.

Star Dreamer · February 21, 2016

I have a jayco motorhome on a Ford E450 chassis, original. Tires Michelin 225/75 with load factor E. max load of the tires is 9880lbs, my actual rear axle weight 9270 (static and motorhome empty with no water, fuel tank 1/3 full) according to Michelin that is asking for tire failure ( had 2 already) because the dynamic loads (going down the street, bumps - uphill - downhill- sideloads) will be over the tire limit. That's the reason the law requires pass, cars and light trucks to have a 16% reserve capacity; mine is down to about 2%. with full fuel and water tank, little bit of staff loaded for vacation or putting anything on the trailer hitch (boat or even loaded bike rack) I am overweight for the existing tires and max rear axle weight I know that is not an issue Ford has to deal but jayco.but I would very much appreciate your expertise about what to do (is that motorhome a risk to drive, maybe unsafe?) is there any means to increase the max rear axle weight on that E450 chassis? any way I could put on a different tire size (enough room on the rim / wheel-well;that would increase the max tire load about 1000lbs - but is that legal and doable, especially. With the dual tires. I am looking forward to your answer. I have doubts to buy new ford or maybe change the motorhome, haven't decided yet.

First off please provide the reference where the law states that you need to have a 16% reserve capacity from the load weights that are published for tires or stamped on the sidewall. There are others that are better experts than we are but I do believe this is incorrect. When we had our individual tire weights done, they only went by the ratings for the tire and did not reduce them by 16%. My feeling is the tire manufacturer would have to do that prior to putting the rating on the tire, in other words the 9880 would already have taken the 16% into consideration if it is the law. Now is it a good thing to reduce the weights to give you a cushion, yes, but it is not law.

You should also have a tag on the chassis that indicates what the maximum RAWR is, which for a E450 is probably around 9800# so the tires provided are good and meet the rear axle rating. If the motorhome empty weighs 9270 as you have indicated on the rear axle, the Jayco is in full compliance. There is nothing that says they have to allow for "X" number of pounds of weight for owner supplied items, water, propane etc... That is one of the bad things about the RV industry. They try to get away with the bare minimums that are allowed and make it very easy for an owner to overload the equipment.

All you can do is try to keep as much items out of the motor home to keep your weight down and as others have said get individual wheel weights to determine where you need to loss weight. You could increase your tire size and gain some reserve capacity there but you still should not exceed the RAWR for the chassis. Sorry for the bad news.

Dave