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Discussion Starter #1 (Edited)
What I thought to be a typo in the specs for Promaster has been posted for over six months.
The tires are described as 225/75R16C BSW for all three trim levels.
Tire load carrying capabilities are as follows:
Load Range: C Maximum Load: 2,205 lbs. Max. Inflation Pressure: 50 psi
Load Range: D Maximum Load: 2,623 lbs. Max. Inflation Pressure: 65 psi
Load Range: E Maximum Load: 3,042 lbs. Max. Inflation Pressure: 80 psi
Gross Vehicle Weight Ratings 1500 8550lbs 2500 8900lbs 3500 9350lbs
Using the rule of thumb that total tire load capacity should be 125% to allow
for weight shifting during cornering and lopsided loading 225/75R16C
tires are not suitable for even the 1500 Model.
The Promaster competitors have 245/75R16E tires.
 

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It's more about the tires' load rating than their size. In Europe they must use higher quality tires because like you, I also noticed they are rated for higher load than the same size tire we would normally use in the US; although I expect that is about to change now.

A quick tire search for a Ducato shows the 225/75R16C has a load rating of 118/116 when used as a single/dual. I think that puts it at 2910 pounds per tire for single applications like ProMaster; which is more than adequate for the one-ton 3500 ProMaster. That assumes of course they'll use a similar tire here.

An example of the different tire load ratings that exist was apparent when Ford published that the new single-wheel Transit would have 235/65R16C 121/119R tires. The load rating for that smaller tire is a little higher than the larger tires on my Ford E350 Econoline.
 

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agreed. the load rating is more important than the size though the size usually increases as the load ratings do.

I'll be waiting to see the official from Ram.
 

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I was curious about this tire issue, so I looked up the specs for the ProMaster that were issued in pdf format a while back. I haven't seen anything newer to contradict this data so I'll use it for the time being.

It appears that all ProMasters beyond the smallest half-ton short-wheelbase model have axle ratings of:

4630 pounds front
5291 pounds rear

Assuming Ram could specify light truck tires as commonly used in US for vans and pickups, Michelin specs (I saved the specs from when I bought my van's tires) show that a 225/75R16 tire has the following load ratings:

225/75R16/D = 110/107 = 2335 pounds at 65 PSI when single

225/75R16/E = 115/112 = 2680 pounds at 80 PSI when single

From this it appears a light truck tire in that size at 80 PSI can meet the maximum axle rating when used as single tires.


For what it's worth for comparison, my Ford E350 van's tires are:

LT245/75R16/E = 120/116 = 3042 pounds at 80 PSI when used as singles.

And the van's rear axle load rating is limited to 6084 pounds which is obviously limited by tire load rating. The front, which uses the same tires, is only rated to carry 3550 pounds (hence much lower tire pressure at front).
 

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Discussion Starter #5
I will not buy a cargo van C rated tires

C rated tires (industry standard rating) are inadequate for the Ram Promaster.
Cargo vans need a margin of safety to allow for loading errors and weight shifting during breaking and cornering.
Competitors have:

Chevrolet Express Cargo 2500 Extended Wheelbase
Max Payload (lbs.)3095.00 lbs GVWR (lbs.) 8600.00 lbs
Tires LT245/75R16E all-season blackwall tires

Ford E-250 SERIES VAN Extended Wheelbase
Max Payload (lbs.)3470 lbs GVWR (lbs.) 9000.00 lbs
Tires LT245/75R16E all-season blackwall tires

Nissan NV2500HD High Roof V6
Max Payload (lbs.)2759.00 lbs GVWR (lbs.) 9100.00 lbs
Tires LT245/70R17E all-season blackwall tires

Sprinter Cargo Vans 2500 144" Wheelbase
Max Payload (lbs.)3362.00 lbs GVWR (lbs.) 8550.00 lbs
Tires LT245/75R16E all-season blackwall tires

I will not buy a cargo van C rated tires
 

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LT225/75R16/C is not the same as a 225/75R16C

These are dIfferent types of ratings. Some manufacturers in Europe rate their 225/75R16C tires at up to a load factor of 121. That's well over 3,000 pounds per tire. More than US common rating for LT245/75R16/E.

I'm sure many buyers will be discouraged by smaller tires regardless of their load rating.
 

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P.S. -- In the first example above, the "C" stands for the common C Load Range of 6 plys that we are familiar with. In the second designation, the "C" appears to stand for "Commercial; tires for light trucks (Example: 185 R14 C)"
 

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P.S. -- In the first example above, the "C" stands for the common C Load Range of 6 plys that we are familiar with. In the second designation, the "C" appears to stand for "Commercial; tires for light trucks (Example: 185 R14 C)"
do you know if there's a speed rating assigned with these tires?
 

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I think it would be very surprising to see a manufacturer include a tire that can't match the cars capabilities. We are just going to have to wait and see.
 

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I think it would be very surprising to see a manufacturer include a tire that can't match the cars capabilities. We are just going to have to wait and see.
there are tires that can get you up to speed and stick with the flow of traffic and limit you their and then other types for people to speed down the highway, which can get expensive. Most should be happy with the stock tires
 

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do you know if there's a speed rating assigned with these tires?
A quick search shows they can vary by manufacturer. I found a couple of "tyres" in UK sites listed with the higher load rating of 121 that have Q or R speed ratings. That corresponds to 100 or 106 MPH if I recall correctly.

I doubt too many commerical vehicles with such high center of gravity will want to speed much faster than that. Regardless, we have to wait to see what tires are actually used because the ProMaster doesn't actually need a tire with a 121 load rating in order to meet its maximum GVWR or maximum axle rating.


By the way, one manufacturer clearly states on their WEB site that their 225/75R16C tire is a "10 PLY", which makes it equivalent to our "E" load-rated tire in US. From this it seems clear the "C" stands for commercial and not for load range normally associated with a 6-ply tire.
 

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Just came back from looking at various ProMasters and took a quick look at tire ratings while there.

The Continental commercial 225/75R16C tires indeed had a load rating of 121/120 which makes them higher than my Ford E-350's E-rated LT245/75R16. Design air pressure was 65 PSI front and 72 PSI rear.
 

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Just came back from looking at various ProMasters and took a quick look at tire ratings while there.

The Continental commercial 225/75R16C tires indeed had a load rating of 121/120 which makes them higher than my Ford E-350's E-rated LT245/75R16. Design air pressure was 65 PSI front and 72 PSI rear.
to your knowledge, how are good are these tires? do you think that tire size is good enough? enough your needs?
 

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to your knowledge, how are good are these tires? do you think that tire size is good enough? enough your needs?
Yes, tire size and load rating are plenty for me. It's over 6000 pounds per axle which exceeds PM's axle capacity front or rear for even the one-ton van. What I don't know is how good they are in wear, traction, and so on.
 

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To resurrect this thread: I just bought a 2017 3500 extended and am surprised to find it has 225/75/ R16 load range E tires rated at 2640lbs, or something like that. I was expecting the heavier 3,000+ lb rated tires. Anyone know what gives?
 
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