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Discussion Starter · #1 ·
Anyone know of a 225 tire other than the vanco that is load rated over 3000 pounds ?

Or do we need to look at 245's?
 

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I am a Michelin guy, and my 16 159ext came with NEXENs. They ride almost as good as the Michelins, and cost 1/2 as much. Won't know how they do on wear, only have 12k on them. I have run the LTX M/S tires for 20+ years and always get 75K= out of them, some have gone 100k. They're E tires so the wt is good. Will let y'all know how they wear as time goes on. I balance and rotate EVERY 5k.
 

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Discussion Starter · #4 · (Edited)
All the e rated tires I looked at in the 225 size only had 2680 lb load. Where the 245 was over 3095, that's a huge difference in load capacity when you multiply that by 4
 

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All I have found with that "code" of 121Q are the Vanco's. I don't think most owners are aware this is NOT a std 225 Load Range E.
 

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Discussion Starter · #6 ·
All I have found with that "code" of 121Q are the Vanco's. I don't think most owners are aware this is NOT a std 225 Load Range E.
That may be, folks the vanco is rated at 3195 pounds.
 

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All the e rated tires I looked at in the 225 size only had 2680 lb load. Where the 245 was over 3095, that's a huge difference in load capacity when you multiply that by 4
For what it's worth, that LT225/75R16 E-rated is the same size Ford uses on E-450 Cutaway motorhome chassis rated up to 14,500 pounds GVWR. Granted there are 6 of them, but if we do the math it's more load per tire than 4 of then on 9,350-pound van.

I know it doesn't necessarily make it a great idea to substitute and give up some safety margin because a sudden rear tire failure in a tall van at speed can lead to an accident. With motorhome's dually arrangement there is a bit more redundancy. However, RAM may have already made the switch.

Last night I was searching the local dealer's inventory and noticed in a picture of door placard that the tires on the van was E rated with 80 PSI on back instead of the previous "C" commercial tire I had seen before.
 

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The Gross Axle Weight Rating for the Promaster is 4,630 pounds Front and 5,291 pounds rear. In order to support the maximum weight rating of 5,291 rear, each tire must therefore be capable of supporting 2,645 pounds. The Promasters now come with the Nexen Roadian CT8 HL, which is rated at 2,680 pounds per tire, which technically makes it sufficient.

Any tire designated for Light Truck, having the LT in its size, with a rating of at least 2,645 will work. But, if you find a tire that does not have the LT rating, and is a P metric or Euro metric size, then it has to have a higher rating to use on the van. LT rated tires are designed for vehicles with a higher center of gravity and a greater ability to carry heavy loads for longer amounts of time. When using a P metric size (225/75-16 versus LT225/75-16) then you have to calculate 91% of the load rating as the maximum. For example, if you find a P metric tire with a rating of 2,700 pounds you would think it is enough, but a P metric tire rated at 2,700 pounds for a car is only rated at 2,700 x 91% = 2,457 pounds when used on a light truck, van, or SUV.

Here's where it gets interesting and specifically applicable to the Promaster. The early Promasters came with a Euro metric 225/75-16C, rated at 3,195 pounds. When used on a light truck, van, or SUV then that tire is actually rated at a maximum load rating of 3,195 x 91% = 2,907 pounds. Still overkill, but not by as much as we originally thought.

To answer Dooman, if you need replacement tires for your Promaster, look for the LT225/75-16 versus the 225/75-16 tire size, and you will see there are plenty of options. On the TireRack.com web site, if you select a 2015 or 2016 Promaster there are 22 tires that come as possible replacements. PerformancePlusTire.com has 93 tires listed in the LT225/75-16 size.
 

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...cut....

Here's where it gets interesting and specifically applicable to the Promaster. The early Promasters came with a Euro metric 225/75-16C, rated at 3,195 pounds. When used on a light truck, van, or SUV then that tire is actually rated at a maximum load rating of 3,195 x 91% = 2,907 pounds. Still overkill, but not by as much as we originally thought.

.....cut....
I'm familiar with derating P-Metric passenger-vehicle tires to 91% when used on light trucks, but the original ProMaster tires were not "P-rated". They are/were specifically designed for truck applications, hence the "C" for commercial use. Besides, P-Metric tires never go up into the 80 PSI range. Not that it really matters anyway because as you say it's an overkill even if it were derated. I just don't think the derating applies to the 225/75R16C as if it were a P225/75R16 tire.

If we had to derate the original 225/75R16C on a PM, then when would it hold it's full rating? It's not like anyone would need or install 3,000-pound-rated tires on a station wagon.
 

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That's quite possible. Having the C for commercial might mean it doesn't get rated at 91%, since it was intentionally made for a van.

Ironically, I've been looking at a used car that is about the same weight as a Promaster but has a higher tow rating of 7500 pounds, that uses this same 225/75-16. It should probably have LT225/75-16 on it instead.
 

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My van will probably never have a total weight of 6500 lbs, as I have lightweight camper built in and don't plan to carry lead bricks anywhere. Can I put on some 225 -C rated tires? What are the issues? Wouldn't they ride better and be up to the task? That is the rating my F150 tires had I believe and I occasionally carried a ton in it for a total of near 7,000 lbs.
 

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Wow! so much information, but really put on some 245/75/16' E's. I went with cooper's ATW's. They ride smooth for a AT, work awesome in snow and mud and the bonus is they look great! Cheers
 

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Wow! so much information, but really put on some 245/75/16' E's. I went with cooper's ATW's. They ride smooth for a AT, work awesome in snow and mud and the bonus is they look great! Cheers
Do they clear all around? Up and down and full steering lock? Have you posted pictures -- can't recall?

That's a very common size -- what I have on old 1-ton van. Common on many older 1-ton pickups too before they started going to 17, 18, and 20-inch tires. The LT225/75R16 E-Rated are also common since they are frequently used on Class C motorhomes and some dually pickups.

Talking about how tire size changes appearance, it's strange to see some Fiat Ducatos with skinny 15-inch tires. They look out of proportion.
 

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Chance, the 245's have plenty of room in the front. They do not even close to rubbing. The rear tires are a different story maybe 1/2" to 3/4" clearance, pretty tight!
I bought Z chains for the front and they look like they will work, have not had to use them yet!
 

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The Cooper AT3 is available in a 245/70-16 which is much closer to the OEM tire diameter.
Is that with an an "E" load rating? Normally the 70 profile tires are not heavy load rated.

Yes they are LT with E load 10ply and have a 2910 pound load carrying capacity per tire so 11,640 pounds total of carrying capacity. See attached image for specs
 

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No, I'm not. I haven't gotten a Promaster yet, but have been on this forum learning whatever I can about them. I will be getting a high roof 159" WB, most likely a 2500 unless I find a smoking deal on a 3500 Extended
 
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