Most Ram 1500 size charts hand you a list and say the rest depends on your trim. What it depends on is two things nobody lays out together: which Ram 1500 you actually own, and which wheel diameter your trim left the factory on. On a 2019-and-newer Ram 1500 (the DT), 18-inch Tradesman and Big Horn trucks run 275/65R18, 20-inch trucks run 275/55R20, 22-inch Laramie, Limited, and Tungsten trucks run 285/45R22, the Rebel runs LT275/70R18, and the TRX and RHO run LT325/65R18. Those five sizes carry load indexes from 113 to 125. And a 2019-2024 Ram 1500 Classic uses different sizes on a five-lug wheel.
Below is every factory size by trim, the rated load behind each one, and the replacement choices that quietly give it away.
Read this table by wheel diameter first and trim name second. Trims on the same wheel share a size, and a trim offered on two wheel diameters has two correct answers.
Ram 1500 Trim |
Years |
Wheel |
Factory Size |
Diameter |
Load Index |
Rated Load per Tire |
|---|---|---|---|---|---|---|
Tradesman, Big Horn, Lone Star (18-inch) |
2019-2026 DT |
18-inch |
275/65R18 116T |
32.1 in |
116 |
2,756 lb |
Tradesman HFE; Big Horn, Laramie, Limited, Limited Longhorn (20-inch) |
2019-2026 DT |
20-inch |
275/55R20 113T |
31.9 in |
113 |
2,535 lb |
Laramie, Limited, Limited Longhorn (22-inch); Tungsten |
2019-2026 DT (Tungsten 2025+) |
22-inch |
285/45R22 114H XL |
32.1 in |
114 XL |
2,601 lb |
Rebel |
2019-2026 DT |
18-inch |
LT275/70R18 125/122R |
33.2 in |
125 (Load Range E) |
3,638 lb |
Warlock (DT) |
2025+ DT |
18-inch |
LT275/70R18 |
33.2 in |
Match your sidewall |
Per load range on sidewall |
TRX; RHO |
TRX 2021-2024; RHO 2025+ |
18-inch |
LT325/65R18 121/118 |
34.6 in |
121 (Load Range D) |
3,197 lb |
Classic Tradesman, Express, Warlock (17-inch) |
2019-2024 Classic |
17-inch |
265/70R17 |
31.6 in |
113 or 115 |
2,535-2,679 lb |
Classic Tradesman, Express, Warlock (20-inch) |
2019-2024 Classic |
20-inch |
275/60R20 114S |
33.0 in |
114 |
2,601 lb |
Rated load is the Tire and Rim Association figure for each load index at the tire's maximum rated inflation. Diameters are calculated from the size and rounded to a tenth of an inch.
The Tradesman's standard 18-inch steel wheels take the same 275/65R18 as an 18-inch Big Horn, and the Lone Star is the Texas-market Big Horn. The Laramie offered 18s in earlier model years, runs 20s as standard in current trucks, and offers 22s. Off-road packages keep the size: the factory all-terrain for the 22-inch trims was the Falken Wildpeak A/T3WA in 285/45R22 114H XL, the same size and load index as the street tire.
The three street sizes sit within two-tenths of an inch of each other, between 31.9 and 32.1 inches. On height alone they look interchangeable. The load index column says otherwise.
From 2019 through 2024, Ram sold two different trucks as the Ram 1500: the redesigned DT and the previous-generation Classic, built alongside it until production ended in 2024. Registration papers and many online size lookups call both of them a Ram 1500, so a 2021 Ram 1500 can mean either truck.
The DT runs a 6x139.7 bolt pattern (6x5.5 inches). The Classic runs 5x139.7 (5x5.5 inches). Neither wheel bolts onto the other truck. Our guides to the 6x139.7 bolt pattern and the 5x139.7 bolt pattern list what else shares each one.
The tire sizes split the same way. A Classic on 17s runs 265/70R17, a 31.6-inch tire. A Classic on 20s runs 275/60R20, a 33.0-inch tire. Compare that with a DT on 20s, which runs 275/55R20 at 31.9 inches. Same model year, same badge, same wheel diameter, and the correct tire differs by 1.1 inches of height.
The trim names make it worse. From 2019 through 2024, Warlock was a Classic trim on 20-inch wheels and 275/60R20 114S tires. For 2025, Ram moved the name to the DT, on 18-inch wheels and LT275/70R18 light truck tires. Search by trim name alone and you can land on the other truck's size.
Telling them apart takes ten seconds. Count the lug nuts: six means DT, five means Classic. Then read the Tire and Loading Information placard on the driver door jamb. It lists the factory size, cold inflation pressure, and occupant and cargo capacity for your specific truck.
A Ram 1500 needs a load index equal to or higher than the one on its factory size. On a 275/65R18 116T, the 116 means 2,756 pounds at maximum rated pressure, and the T is the speed rating.
Here is the detail most size guides leave out. A 20-inch truck on 275/55R20 113T carries 2,535 pounds per tire. The same truck on 18-inch wheels and 275/65R18 116T carries 2,756. That is 221 pounds less per tire, or 884 pounds across four, at nearly identical height.
The mechanism is air volume. A tire carries load with the air inside it, and at a given pressure more air carries more weight. The 275/65R18 has a 7.0-inch sidewall. The 275/55R20 has 6.0 inches, holds less air, and earns a lower index. The 285/45R22 is down to 5.0 inches, which is why Ram specifies XL (extra load) construction. XL tires run a higher maximum inflation, around 42 psi versus about 36 psi for a metric standard-load tire, and that pressure buys the capacity back to 114.
Ram set each truck's payload and towing numbers with its factory tire in the calculation. Under FMVSS 110, the federal tire selection standard for vehicles up to 10,000 pounds, the manufacturer must fit tires rated for the vehicle's maximum load and post the door placard. NHTSA's replacement guidance follows: match the placard size and carry at least the same load capacity. Your axle ratings do not change when you change tires. Your margin under them does.
That margin matters most at the rear axle, where bed payload and trailer tongue weight land. Our breakdown of load range vs. load index covers how the index converts to the load range letters on LT tires.
Match the speed rating too. The 18- and 20-inch street tires are T-rated (118 mph). The 22-inch tires are H-rated (130 mph). The Rebel's LT tire is R-rated (106 mph). A T-rated 22 on a Limited is a step down from what Ram specified, even if the load index lines up.
You can, but it is not a like-for-like replacement. The DT's factory street tires are metric sizes with no P in front. A P-metric tire in the same numbers usually carries a lower index, and then it gets derated on a truck.
P-metric load indexes assume passenger-car service. On a pickup, SUV, or trailer, the Tire and Rim Association load tables and the federal tire selection rules divide that rating by 1.10 to hold a reserve for truck duty. Metric tires without the P, the kind Ram fits, do not take that division.
Run the numbers on the most common DT size. A P275/65R18 typically carries a 114 index, 2,601 pounds, which counts as 2,365 pounds on your Ram. The factory 116T carries 2,756. That is 391 pounds short per tire, 1,564 across the set, on a tire that looks identical. A P275/55R20 111 counts as 2,185 pounds, 350 short of the factory 113.
This table lays out each Ram 1500 size by construction, so you can see which versions keep the factory capacity.
Size |
Factory Spec |
P-Metric Version |
Metric or XL Version |
LT Version |
|---|---|---|---|---|
275/65R18 |
116 (2,756 lb) |
114: 2,601 lb, counts as 2,365 lb on a truck |
116 (2,756 lb) |
123 Load Range E (3,415 lb) |
275/55R20 |
113 (2,535 lb) |
111: 2,403 lb, counts as 2,185 lb on a truck |
113 (2,535 lb) or 117 XL (2,833 lb) |
120 Load Range E (3,086 lb) |
285/45R22 |
114 XL (2,601 lb) |
110: 2,337 lb, counts as 2,125 lb on a truck |
110 SL (2,337 lb) or 114 XL (2,601 lb) |
Rarely made |
275/70R18 |
LT 125, Load Range E (3,638 lb) |
116 (rare): counts as 2,505 lb on a truck |
116 SL (2,756 lb) |
125 Load Range E (3,638 lb) |
325/65R18 |
LT 121, Load Range D (3,197 lb) |
Not made |
Not made |
121 Load Range D (3,197 lb) or 127 Load Range E (3,858 lb) |
265/70R17 (Classic) |
113 or 115 |
113: 2,535 lb, counts as 2,305 lb on a truck |
115 SL (2,679 lb) |
121 Load Range E (3,197 lb) |
275/60R20 (Classic) |
114 (2,601 lb) |
114: 2,601 lb, counts as 2,365 lb on a truck |
115 SL (2,679 lb) or 116 XL (2,756 lb) |
123 Load Range E (3,415 lb) |
Two market facts stand out. In 275/55R20, the XL 117 is one of the most common replacements, and it beats the factory 113 by 298 pounds per tire. In 285/45R22, standard-load 110 tires sit alongside the XL 114s and look identical until you read the sidewall. A 110 on a Limited or Tungsten is 264 pounds per tire under spec.
Our P-metric vs. LT tires guide runs the towing math on both constructions.
The Rebel leaves the factory on light truck tires: LT275/70R18 125/122R, Load Range E. LT construction adds plies and tougher sidewall compounds that resist the punctures and cuts trail use brings. At 3,638 pounds per tire, it out-carries every DT street size by at least 882 pounds.
The 125/122 is a dual rating: 125 for single wheels, which every Ram 1500 runs, and 122 for dual rear wheels, which do not apply. The R speed rating is 106 mph.
Replacement is where the LT spec gets lost. Nearly every 275/70R18 on the market is LT Load Range E, but a few passenger-construction versions exist at a 116 index, 2,756 pounds. On a Rebel, that gives up 882 pounds per tire plus the sidewall toughness the trim was built around. They fit. They are not a Rebel tire.
Pressure is the other half. An LT tire reaches its rated load only at maximum inflation, 80 psi for Load Range E. At the Rebel's lower placard pressure it carries less, and Ram calculated payload at placard pressure. Inflate to the placard for daily driving and use the owner's manual for loaded-towing adjustments.
The 2025 DT Warlock shares the LT275/70R18 size. Match the load range on your sidewall when you replace them.
Yes. Ram does it at the factory. The 275/65R18, 275/55R20, and 285/45R22 all measure 31.9 to 32.1 inches tall, so a DT moves between 18, 20, and 22-inch wheels with under 1 percent speedometer change and no change in ride height.
What changes is sidewall and capacity. Going to 20s cuts the sidewall from 7.0 to 6.0 inches and the load index from 116 to 113. Going to 22s cuts it to 5.0 inches and requires XL to reach 114. Shorter sidewalls sharpen steering response, and they give up cushion over potholes and protection for the wheel lip.
That makes downsizing a real option. A 20-inch Big Horn or Laramie that tows regularly can move to 18s on 275/65R18 116 and gain 221 pounds of rated capacity per tire at the same height. The 18-inch wheel is the smallest factory diameter on the DT, so that is the floor.
If you move up to 22s, buy XL. The XL load range is what lets a low-profile tire carry truck weight, and a standard-load 285/45R22 gives up 264 pounds per tire. Match the H speed rating while you are there.
Factory DT wheels in all three diameters run close to +19 mm offset. Aftermarket 6x139.7 wheels range from high positive to deep negative. A 20x9 at +19 and a 20x10 at -24 put the same tire in very different places, so check offset before you assume a tire that fits on OE wheels fits on yours.
Not at stock height on factory wheels. The TRX (2021-2024) and RHO (2025 and later) run LT325/65R18 tires, 34.6 inches tall and about 12.8 inches wide. The RHO's factory tire is a Goodyear Wrangler Territory AT, 121/118T, Load Range D.
Ram built those trucks around that tire, with about six inches more track width, wider fenders, and on the RHO, two inches more ride height than the rest of the lineup. A Big Horn or Laramie has none of that, so the question becomes a lift, leveling, and offset problem. We worked through it in will 35s fit a Ram 1500 with a leveling kit, including the coil versus air suspension split.
On the TRX and RHO themselves, watch the load range. The factory Load Range D carries 3,197 pounds at 65 psi. Most replacement 325/65R18s are Load Range E, 127, rated 3,858 pounds at 80 psi. The E is in spec, but it is built stiffer and typically rides firmer at the same pressure. If you want the factory ride, look for the D.
A wrong tire rarely announces itself on the first drive. It costs you in steps, and each one costs more than the last.
Mount a Classic's 275/60R20 on a DT that should run 275/55R20 and the tire is 3.4 percent taller. At an indicated 65 mph you are doing about 67, and the odometer, transmission, ABS, and stability control all read a wheel speed that no longer matches the truck.
A derated P-metric tire or a standard-load 22 flexes more under the same load. You feel it as sidewall squirm with a trailer on the hitch. Go the other way, LT Load Range E on a Laramie, and you get a harder ride and more unsprung weight than the truck was tuned for.
A tire running near or past its rated capacity flexes more every revolution, and flex makes heat. Heat breaks down rubber and the bond between belts and casing. On a loaded rear axle on a hot highway, nothing on the dashboard tells you it is happening.
Overloaded sidewalls crack, bulge, and scuff faster. Once you see a bulge or cut, our guide on tire sidewall damage and whether it is safe to drive on covers what can stay on the truck and what comes off now.
The end of the ladder is a set of four replaced early, with usable tread left, because it was the wrong size or rating for how the truck gets used. Buying the right size and load index the first time is the cheapest option on this list.
Five minutes in the driveway removes every guess.
Ram 1500 tire size by trim is really tire size by wheel diameter and by truck. On a DT, 18-inch trims run 275/65R18 116, 20-inch trims run 275/55R20 113, and 22-inch trims run 285/45R22 114 XL. The Rebel runs LT275/70R18 Load Range E, and the TRX and RHO run LT325/65R18 Load Range D. A 2019-2024 Classic is a different truck with its own sizes on a five-lug wheel. The size gets you close. The load index, construction, and bolt pattern get you the right tire.
A 2019-and-newer Ram 1500 comes on 275/65R18, 275/55R20, or 285/45R22 depending on wheel size, with LT275/70R18 on the Rebel and LT325/65R18 on the TRX and RHO. A 2019-2024 Ram 1500 Classic uses 265/70R17 or 275/60R20.
A DT Big Horn runs 275/65R18 116T on 18-inch wheels or 275/55R20 113T on 20-inch wheels. The 18-inch size carries 221 pounds more per tire, so match the load index on the wheel size your truck has.
The DT Rebel runs LT275/70R18 125/122R, Load Range E, on 18-inch wheels. It stands about 33.2 inches tall and carries 3,638 pounds per tire at 80 psi.
Most DT Laramies run 275/55R20 113T on 20-inch wheels. With 22-inch wheels, the size is 285/45R22 114H XL. Early Laramies also offered an 18-inch option on 275/65R18.
No. The 275/55R20 is the DT size at 31.9 inches tall. The 275/60R20 is the Ram 1500 Classic size at 33.0 inches tall. Swapping one for the other changes speedometer accuracy by about 3.4 percent.
No. The Ram 1500 Classic uses a 5x139.7 bolt pattern and the DT uses 6x139.7. The wheels do not interchange in either direction.
