Tire question? Need some help before I drop a grand. Very soon

It's tire time. I have a 03 3500 2WD Nothing fancy other than air bags and a sway bar. Front end was completely rebuilt 2 years ago. MM3 Beta Tuner

I am replacing the 4 tires on my truck. I get them pretty cheap from a fellow engineer who went to tires. My goal is to lower the RPM about 100+ at highway speed. This thing feels like it needs another gear. @F350Cummins agrees with that. It's also time to get all 4 the same.

I already have 3.42 rear gears. The engine sweet spot is between 1500 and 1600
I found a formula to figure it out, but of coarse, cost is a factor. https://www.ringpinion.com/calculators/Calc_RPM.aspx
265/70/17 31.6 tall 1762 RPM at 70 MPH 10.7 wide (1655 RPM at 65)
285/70/17 32,7 Tall 1722 RPM at 70 MPH 11.5 wide (1599 RPM at 65)
285/75/17 33.9 Tall 1661 RPM at 70 MPH 11.3 wide 2.3" taller than stock (1542 RPM at 65)
315/70/17 34.3 Tall 1637 RPM at 70 MPH 10" wide 2.8" taller (1520 RPM at 65)

The 315's offer the lowest RPM, but almost 3" taller. Since this is 2 wheel drive, I'm not as high as you other guys. I am concerned about rubbing. The 315's offer the best payback and the narrowest tread. Not sure the the stock rims can handle the 315's either. I'm going to turn the wheels and measure the clearance.

I'm looking for opinions/ideas/suggestions before I pull the trigger. $1000 doesn't come easy here.
@Double R Diesel Does the MM3 have tire size adjustment? I never looked

Probably the last set of tires I will ever buy.

I know that the front suspension has changed over the years but I am betting the same things that cause tire rub on my '12 are probably in the way on your '03. I did tons of research when I bought my last set of tires and being within 10k of needing them again I have started back up again. Here is what I found to be true so far....

Assuming 265s are on there now, 285/70 is probably your​ most cost effective option. They will fit the stock rim and fill the wheel wells nicely all without out any rubbing. Also, these are a common tire size and can be found in most MFG line up of tires.

If you have the room in the budget (and wheel wells) 285/75 will give you the extra height without increasing width over 285/70. But, this so a less common size and are a bit harder to find in a true E-rated tire.

315/70s give the most height but are very wide. . They are often compared to 35/12.5. Expect them to rub, especially on a 2wd truck.

I run 305/70s which is same height as 285/75 but 12" wide and they​ rub on occasion when turning hard left. I will probably get these again unless I decide to get new rims when tires are due.

I hope some of this helps.

Greg
2012 | RAM 2500 | CCSB | Custom tuned by Double R Diesel
2016 | Heartland Pioneer | DS310

I agree with Power247. I would go with 285/75/17; it's still in your sweet spot and it's not too wide at about 11". 315's are about 12-12.5" wide, i think that is too wide for factory wheels. The wider the tire the more fuel consumption as well. Toyo is an awesome brand

Oh, and yes the mm3 lets you calibrate tire size :)

Quote:

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Originally Posted by Power247

I know that the front suspension has changed over the years but I am betting the same things that cause tire rub on my '12 are probably in the way on your '03. I did tons of research when I bought my last set of tires and being within 10k of needing them again I have started back up again. Here is what I found to be true so far....

Assuming 265s are on there now, 285/70 is probably your​ most cost effective option. They will fit the stock rim and fill the wheel wells nicely all without out any rubbing. Also, these are a common tire size and can be found in most MFG line up of tires.

If you have the room in the budget (and wheel wells) 285/75 will give you the extra height without increasing width over 285/70. But, this so a less common size and are a bit harder to find in a true E-rated tire.

315/70s give the most height but are very wide. . They are often compared to 35/12.5. Expect them to rub, especially on a 2wd truck.

I run 305/70s which is same height as 285/75 but 12" wide and they​ rub on occasion when turning hard left. I will probably get these again unless I decide to get new rims when tires are due.

I hope some of this helps.

Greg
2012 | RAM 2500 | CCSB | Custom tuned by Double R Diesel
2016 | Heartland Pioneer | DS310

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Thanks Greg

As an after thought I threw in the 315 just to mess with ya. LOL But it brought up an interesting point. But I agree, they are going to be too big.

The 75 series are available in the warehouse here. But they are more expensive. like $50.00 more per tire. The 315 is about the same as the 75's. So you can see where my old fart thinking is. I'm trying to be practical and functional. There's so many options. . . . I forget what the stock rim size it. (I've forgotten soo much) The 315's use a 7 to 9" wide rim.

Keep the info coming

@lcarrasco Thanks

I know where to get a 285 75 r17, its what I had on my silver truck @Polaraco. it may be a little aggressive, but you may recall when you drove that truck they werent very loud.

Quote:

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Originally Posted by F350Cummins

I know where to get a 285 75 r17, its what I had on my silver truck @Polaraco. it may be a little aggressive, but you may recall when you drove that truck they werent very loud.

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I got my buddy Dennis up there at economy tire. There are nonaggressive designs too.

BTW, We're not here all day

Quote:

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Originally Posted by Polaraco

Thanks Greg

As an after thought I threw in the 315 just to mess with ya. LOL But it brought up an interesting point. But I agree, they are going to be too big.

The 75 series are available in the warehouse here. But they are more expensive. like $50.00 more per tire. The 315 is about the same as the 75's. So you can see where my old fart thinking is. I'm trying to be practical and functional. There's so many options. . . . I forget what the stock rim size it. (I've forgotten soo much) The 315's use a 7 to 9" wide rim.

Keep the info coming

@lcarrasco Thanks

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I agree its crazy that 315s price is almost the same as the 285/75s. Like @lcarrasco said, fuel milage will be a factor with the 300 series tires as well.

Greg
2012 | RAM 2500 | CCSB | Custom tuned by Double R Diesel
2016 | Heartland Pioneer | DS310

I don't think that there are two many on this forum is getting away for less then $ 1000.00 for four tires of any kind of name brand or quality tire for that price I mean usually looking from $ 1200 - $ 1500 for a set of four in my experience :rockon::grd::grd::clogo::rambo:

Just be careful my friend. You can make it fast and powerful, but there are two things I'm extremely picky on.

Tires and brakes.

Tires are normally the only thing between the road and you. And I always trend towards quality.
Brakes are the only control stopping you have besides a wall or another vehicle .. and I ALWAYS do my own break job.

Just keep this in your mind when buying !