2017 (or thereabout) Rebel Load & Inflation Placard

[Daniel Ortiz]

Howdy! So I'm trying to better understand the tire pressures FCA decided to go with for the Rebel, especially that 55/45 split (did anyone figure that out?), as well as for the regular 1500s like my own. I've searched around a decent amount but can't find any images of the 2017 (or thereabout) Rebel loading and tire inflation placards (the ones on the door).

If anyone with that year Rebel, or a similar year, can post an image of their placards, or just transcribe the information in a post, that would be swell.

Alternatively, if the Rebels placard info simply follows the general towing tables Ram puts out, then I guess I have access to those already. Let me know your thoughts and input, and thanks for any help you can give!

 

[blackbeautyhemi]

2017 rebel

 

[Daniel Ortiz]

2017 rebel

Much appreciated BlackBeautyHEMI. Looks like it indeed follows the Ram Towing Charts, including their 100 lb knockdown on GVWR for having the heavier tires (6800 lb instead of 6900 lb).

So my 2017 Express has the same GAWR font and back (3900 lb). It's OE fitment was P275/60R20 @ 39 psi front & back, for a load capacity of 2601 lb/tire per T&RA load tables. That gives each axle's two tires a load capacity of 4729 lb after losing the 10% safety factor added for the P-rated tires (2601 / 1.1 x 2), which is about 21% over the GAWR of 3900 lb. That makes sense, to have about 20% margin in tire load capacity over what's needed for the GAWR.

The 2017 Rebel also has the same GAWR front and back (3800 lb). Its OE fitment gives a load capacity of 2900 lb/tire front, 2510 lb/tire rear, for total load capacity of 5800 lb front, 5020 lb rear, which is a margin of 53% front, 32% rear over the GAWR. Quite a bit more margin than the regular Express.

Either they think Rebel owners are going to overload the heck our of their Rebels, or they think they'll drive them all crazy like, necessitating the increased handling performance of higher pressures rather than the increased load capacity. Based on the 55 front over the 45 rear, I'm guessing they think you all are crazy drivers.

That's going to me my own answer for the 55/45 psi split.

 

[blackbeautyhemi]

Yea you put way more thought into it than I ever have lol. I just assumed the higher pressure was for having smaller 17” rims, more sidewall so it wasn’t as firm of a sidewall requiring more air for rigidity? Lol but I drive normal most of the time but I did buy a truck named a rebel so at times I am a bit of a rebel behind the wheel of a hemi haha

 

[Daniel Ortiz]

Yea you put way more thought into it than I ever have lol. I just assumed the higher pressure was for having smaller 17” rims, more sidewall so it wasn’t as firm of a sidewall requiring more air for rigidity? Lol but I drive normal most of the time but I did buy a truck named a rebel so at times I am a bit of a rebel behind the wheel of a hemi haha

Alas, it's the engineer in me. You should hear my wife complain about it sometimes. Things tend to get done perfectly or not at all. I struggle.

Your theory about the larger side wall has merit, except that the Tradesman comes with 17" wheels too, and P265/70R17 113R OE tires set to 40 psi front and rear, which is in the "makes sense" range. Since the Tradesman follows the same GAWRs as the rest of us, if they don't need the extra wacky pressure, I don't see why the Rebel does either, except that they consider the Rebel a "high performance" vehicle likely to get driven hard and fast. It sure would be interesting to talk to the FCA/Ram engineers who pegged those tire pressures as the official ones, to see why they did so.

Anyway, enough nerdery here. Thanks for your help man. Take care.

P.S.
Another thought occurred to me. The Rebel is the only Ram 1500 with factory ride heights greater than the rest of the trim levels (+1" normal, +2" off road), which could lead to increased risk of rollover if the tires weren't firm/rigid enough. That may be why they increase the tire pressures, especially in the front where you'd want that extra stiffness to prevent rolling if you made a high-speed maneuver in an emergency. By Jove! Now I think that's the reason why.

 

[blackbeautyhemi]

Alas, it's the engineer in me. You should hear my wife complain about it sometimes. Things tend to get done perfectly or not at all. I struggle.

Your theory about the larger side wall has merit, except that the Tradesman comes with 17" wheels too, and P265/70R17 113R OE tires set to 40 psi front and rear, which is in the "makes sense" range. Since the Tradesman follows the same GAWRs as the rest of us, if they don't need the extra wacky pressure, I don't see why the Rebel does either, except that they consider the Rebel a "high performance" vehicle likely to get driven hard and fast. It sure would be interesting to talk to the FCA/Ram engineers who pegged those tire pressures as the official ones, to see why they did so.

Anyway, enough nerdery here. Thanks for your help man. Take care.

P.S.
Another thought occurred to me. The Rebel is the only Ram 1500 with factory ride heights greater than the rest of the trim levels (+1" normal, +2" off road), which could lead to increased risk of rollover if the tires weren't firm/rigid enough. That may be why they increase the tire pressures, especially in the front where you'd want that extra stiffness to prevent rolling if you made a high-speed maneuver in an emergency. By Jove! Now I think that's the reason why.

Lol yea I can imagine if you put as much thought into some things as you just did in tire pressure reasoning, you and your wife have some interesting conversations haha. But in all seriousness what ya said made sense and gave me a good perspective on the technical side of it. I’m sure if you talked to a fca engineer about tire pressure tho, you might be one of the first to bring that topic, of all topics, up to them lol glad I could help tho!