The Nitto Ridge Grappler in size LT305/65R18 is a hybrid-terrain radial tire with a 128/125Q service description. The Ridge Grappler is Nitto’s hybrid-terrain option, positioned between an all-terrain and a mud-terrain tire.
Size and wheel specifications
- Tire size: LT305/65R18
- Manufacturer stock number: 217520
- Wheel diameter: 18 in
- Nominal section width: 305 mm
- Load index / speed rating: 128/125Q
- Load designation: Load Range F (12-ply rating)
- Approved rim-width range: 9.0–11.0 in
- Measuring rim width: 9.0 in
- Manufacturer-listed overall diameter: 33.58 in
- Manufacturer-listed overall width: 12.24 in
- Tread depth: 16.4/32 in
- Maximum load / inflation rating (single-tire application): 3,970 lb at 80 psi
Nitto lists this exact stock number at 33.58 inches overall diameter and 12.24 inches overall width on the 9.0-inch measuring rim. The measuring rim is the reference for those published dimensions; the approved rim-width range is 9.0–11.0 inches.
The 128/125 load index lists 128 for single-tire use and 125 for dual-tire use. These ratings apply to different installation arrangements. The maximum-load figure above is the single-tire rating; do not use it as a dual-installation capacity.
Before ordering
Compare the complete size, load index and speed rating with your vehicle’s approved requirements. Confirm wheel width, wheel load capacity and clearance as well as diameter. A tire’s dimensions do not establish an OEM vehicle application. If changing tire size or type, have the combination and operating pressure checked by a qualified tire professional.
Questions about LT305/65R18
What do the numbers in LT305/65R18 mean?
The size uses a nominal 305 mm section width and an aspect ratio of 65; the sidewall height is expressed as a percentage of that nominal width. R denotes radial construction and 18 is the wheel diameter in inches. Nitto lists this exact tire at 33.58 inches overall diameter and 12.24 inches overall width on the 9.0-inch measuring rim. LT identifies the light-truck size designation.
What wheel width is approved for this LT305/65R18 tire?
Nitto lists 9.0–11.0 inches as the approved rim-width range for stock number 217520. Its 9.0-inch measuring rim is the reference for the published dimensions, not the only approved width. The wheel must also have the correct 18-inch diameter and be suitable for the vehicle and required load.
Does Load Range F mean this tire contains 12 physical plies?
No. Load Range F corresponds to a 12-ply rating, a load/strength classification rather than a count of physical cord layers. This tire’s service description is 128/125Q. The load index is 128 in a single-tire application and 125 in a dual-tire application; Q is the speed symbol.
Is 80 psi the pressure I should run in this tire?
No. The listed 3,970 lb at 80 psi is Nitto’s maximum load/inflation rating for a single-tire application. It is not a recommended pressure for every vehicle. Follow the applicable vehicle and tire guidance, and have the operating pressure confirmed when changing tire size, type or load requirements.
Will this LT305/65R18 tire fit any vehicle with 18-inch wheels?
No. A matching 18-inch wheel diameter is only one requirement. Check the approved 9.0–11.0-inch rim-width range, complete 128/125Q service description, wheel load capacity and vehicle clearance. The published 33.58-inch diameter is useful for comparison, but does not prove vehicle fitment or that a lift or modification is unnecessary.
