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We carry alot of weight in our plumbing trucks 3500's.The rears sag a bit and im curious if anyone here has had leafs added and if so what was the ride like after. Also did it have a positive affect on the front tires traction? Thanks guys
 

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Can't recall anybody adding leaf springs...

There's a couple of posts about adding air bags, one as part of a suspension lowering.
 

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We carry alot of weight in our plumbing trucks 3500's.The rears sag a bit and im curious if anyone here has had leafs added and if so what was the ride like after. Also did it have a positive affect on the front tires traction? Thanks guys
Justin, I'm curious how much sag you are experiencing, and also how much weight it took to get it to squat enough that you'd want to change it.

There have been many comments about the ProMasters' rear end being jacked-up too high from factory, but none I recall about being too low under load. I can't help you in that I don't even own a PM yet, but you could help some of us by sharing more information, or perhaps a picture of the loaded van from the side. I say this only because some prospective buyers may be looking at 2500 in lieu of 3500 to get softer springs, which may not be a good idea depending on load.


The one thing I can share is that making the rear springs stiffer by adding a leaf can't change the weight distribution enough to even notice, and hence won't affect traction on relatively level ground. In theory, stiffer rear springs may reduce body roll so that front tires remain loaded more equally, but thinking that would be enough to improve traction would be a stretch in my opinion.

If it's a serious issue, I strongly recommend weighing your van on truck scales first before making modifications. It's a common practice with RVers to get load right. For example, you don't want to be overloading suspension or tires. Without weighing it can often involve too much guessing.
 

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I could be wrong Chance, but I believe

1500 - Base Model
2500 - heavier springs
3500 - bigger rear brakes.

So I'm pretty sure the 2500 and 3500 come with the same springs.

Anyone else want to chime in? This is how my dealer described it to me when I was purchasing.
 

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I could be wrong Chance, but I believe

1500 - Base Model
2500 - heavier springs
3500 - bigger rear brakes.

So I'm pretty sure the 2500 and 3500 come with the same springs.

Anyone else want to chime in? This is how my dealer described it to me when I was purchasing.
I had the Ford Fleet Manager tell me at a recent RV Show that the Transit only came with 3.7L V6. I had to inform him that they also came with 3.2L diesel and 3.5L EcoBoost. It's sad that many of these guys know very little about their products.

ProMaster specs show rear axles are rated the same for most models except the very smallest (short-wheelbase low-roof 1500) so I'd be very surprised if brakes are different. It wouldn't make sense from a cost standpoint because they'd have to inventory more parts to save pennies.

The leaf springs, on the other hand, normally don't require replacement, so there is little need to manufacture or inventory different models beyond the factory in Mexico. Springs are not normally wearable parts.

Looking at detail specs of my current Ford van shows they came with numerous spring ratings depending on body style and or GVWR. I even have Ford data on coil spring gauge sizes for the front.

It's possible your dealer is correct, but it wouldn't assume much unless I saw it in writing. And even then we should question some data because much from both RAM and Ford on these new vans has been incorrect.
 

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This week, i hauled a 3600# diesel engine in the pm. I have a hand winch inside that i can use to tug a load forward for better balance, but didnt want to mess with it on this run. With that load centered over the rears, there was a touch of lift at the front end, more wander, and the truck was more at yhe mercy of groovesin the road. Still, not pronounced or objectionable from the dry handling.

Conclusion? A cheap set of helper springs wouldbolt on and do as advertised. Im quite liberal with load, and dont have an issue with being overloaded (within reason). I would woory more about the tires getting hot overloaded at high speed than
I would about anything else.
 

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Justin,

I've had extra leafs put in and older E150 I used for plumbing a few years ago. You should be able to find a local place to either add a leaf or recurve your vans.
My Promaster is more a special projects van for me to drive. I'm not going to let my guys beat this one to death. Good luck, Todd
 

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I think the 118" comes with light springs, my 1500 136" says it came with a medium duty suspension.

Speaking of which, I have bit loaded on my drivers side compared to my passenger side and on level ground it looks tilted that way, anyone else experience this?
 

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I could be wrong Chance, but I believe

1500 - Base Model
2500 - heavier springs
3500 - bigger rear brakes.

So I'm pretty sure the 2500 and 3500 come with the same springs.

Anyone else want to chime in? This is how my dealer described it to me when I was purchasing.
Based on the parts microfiche, there are 5 different leaf springs listed for the 2500 and 3500 models and two different calipers and rotors. The parts fiche lists "with HD brakes" and "without HD brakes" as the difference for both rotors and calipers. I've never seen an option for HD brakes, so I assume it is either part of the towing package or perhaps the RV package. If I had to guess I would say the 5 different leaf springs are to accommodate the different body designs, like low roof, high roof, high roof extended, etc.

It would be nice to find a dealer sales rep who actually knows these things. A few years ago I was able to get a dealer copy of a Sprinter order manual, which had every code for every option. The towing package for instance listed a dozen codes for stuff that came with it, and you could find every code in that book to see what it was. I'd like to see what changes on a Promaster when I add certain options.

What I did find interesting is that the rear way bar that comes with the 3500 also comes with the 2500 Window van, but not any other 2500's.
 

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Sarness, I believe all 1500's have the same springs short or long wheel base, They all have the same 8550 gvwr.. 2500 is 8900 gvrw and 3500 is 9350 gvrw... Is there a rear spring uprade option?
 

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Based on the parts microfiche, there are 5 different leaf springs listed for the 2500 and 3500 models and two different calipers and rotors. The parts fiche lists "with HD brakes" and "without HD brakes" as the difference for both rotors and calipers. I've never seen an option for HD brakes, so I assume it is either part of the towing package or perhaps the RV package. If I had to guess I would say the 5 different leaf springs are to accommodate the different body designs, like low roof, high roof, high roof extended, etc.

.....cut.......
Did you happen to notice how many front springs they listed? I'm guessing that with gas and diesel weighing differently there could also be a few in addition to van models.
 

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Did you happen to notice how many front springs they listed? I'm guessing that with gas and diesel weighing differently there could also be a few in addition to van models.
I just looked, and the same part number is listed for 1500, 2500, and 3500 models, for both gas and diesel.

That seems strange to me. I wonder if there is a suffix to the part number that gets added by the dealer based on your VIN or model code? While it doesn't seem impossible to me, it does seem a little strange that the 1500 gas and 3500 diesel would have the same front coil spring.
 

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3500 leans to drivers side

Sharness, I have the same problem with my 3500 leaning to the drivers side.
I have several other vans loaded similar and they did not lean. I asked about it at the dealer he said I had to redistribute the load. I ordered Timbren Rear Suspension Enhancement System, I will install them next week when they come in.
 

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I think the 118" comes with light springs, my 1500 136" says it came with a medium duty suspension.

Speaking of which, I have bit loaded on my drivers side compared to my passenger side and on level ground it looks tilted that way, anyone else experience this?
My 159/2500 leans to the drivers side a bit. I just figured it's because I have more cabinets and weight on that side after my conversion. It's only noticeable when it's parked in my garage, not on the road. Doesn't really bother me enough to try and correct it tho.
 

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Dynamax REV 24RB Rear loaded to the MAX

Dynamax engineering said my new REV 24RB Class C motorhome weighed 2565 lb dry weight on right rear tire when shipped from factory. Rear axle GAWR is 5291 lb / 2 = 2645 lb allowable for rear tire. It is my responsibility to stay within load ratings so I can only carry 54 lb of cargo in right rear. The floor is level so springs are balanced but I wonder if adding a leaf or Timbren would help. When I drove home from Nola Monday they had 30mph gusts and it felt very rocky at 70 mph.

The other problem is tires. TireMart said use 80psi not door sticker 72psi. He could not find any optional tire to help tire load rating.
 

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Dynamax engineering said my new REV 24RB Class C motorhome weighed 2565 lb dry weight on right rear tire when shipped from factory. Rear axle GAWR is 5291 lb / 2 = 2645 lb allowable for rear tire. It is my responsibility to stay within load ratings so I can only carry 54 lb of cargo in right rear. The floor is level so springs are balanced but I wonder if adding a leaf or Timbren would help. When I drove home from Nola Monday they had 30mph gusts and it felt very rocky at 70 mph.



The other problem is tires. TireMart said use 80psi not door sticker 72psi. He could not find any optional tire to help tire load rating.

You have a REV! Please tell us about it. I think the Timbren or Sumo Springs solution will help as the Sprinter conversion guys seem to like the Sumo Springs.



Sent from AutoGuide.com Free App
 

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I love the REV; nice floorplan and easy to drive. We use it as a van with kitchen sink and bath but I think you could camp with 2 people and small kids?

My problem is I can't use it without exceeding rear GAWR and overloading the tires. Dynamax is deceptive because I asked tech support about how they define cargo capacity before buying it and they only stated the sticker CCC. The Fed sticker doesn't have front CCC and rear CCC. They didn't tell me I need to place ALL my cargo and passengers between the front two seats.
 

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I love the REV; nice floorplan and easy to drive. We use it as a van with kitchen sink and bath but I think you could camp with 2 people and small kids?

My problem is I can't use it without exceeding rear GAWR and overloading the tires. Dynamax is deceptive because I asked tech support about how they define cargo capacity before buying it and they only stated the sticker CCC. The Fed sticker doesn't have front CCC and rear CCC. They didn't tell me I need to place ALL my cargo and passengers between the front two seats.
What is your cargo carrying capacity?

If rear axle is at maximum, I expect the CCC can't be much before the 9350 pound GVWR is exceeded.

By the way, I saw the Rev at two RV shows and the rear did look heavy. I recall the rear tires looking squashed down more than other PM Class B+.
 

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Dynamax REV 24RB Rear loaded to the MAX

What is your cargo carrying capacity?

If rear axle is at maximum, I expect the CCC can't be much before the 9350 pound GVWR is exceeded.

By the way, I saw the Rev at two RV shows and the rear did look heavy. I recall the rear tires looking squashed down more than other PM Class B+.
Dynamax REV 24RB engineering is deceptive or fraudulent. I called and asked how they calculate CCC before I bought it and blew me off until I got the dealer on 3way. Then they said GVWR - Dry Weight = CCC only total vehicle weight numbers. They intentionally avoided telling me the individual wheel dry weights they record for every RV at the factory. I only knew CCC = 1108 lb. If I had known Rear CCC = 100 lb and front CCC = 1000 lb I wouldn't have bought it and could have saved $62000 mistake and potential lawsuit. With no water, gas, propane, cargo or passengers, as soon as I step in the rear door the rear axle exceeds GAWR.
 
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