Wheel offset and backspacing


Wheel offset and backspacing.

Okay so you finally decided you want to get rid of the puny looking tires on your truck and took a lot of time looking at the pictures on this site - your choice is made!

Wheee ha, just the idea of how your truck will perform gets your heart racing - yea, yea we know the feeling, but hold on: Are you seriously going to fit those new rubber doughnuts on the cheesy looking factory wheels?
No sir, never - they might not even fit on those narrow biscuit-cutters.
Hold your horses, before you charge off to order a set of wheels for those tires you need to know a few things - hey you do want those rims to actually fit and be road-legal, yes? 

In some kind of order you need to look at the rim diameter and width - a quick look at the tire catalogue will show you the rim sizes that will work with the tire size you intend to buy - my advice is to stay conservative with your rim width...
If you decided on a width the next step will be to find a rim with the correct bolt-pattern (pcd) for your truck, then you need to calculate what rim-offset will keep the wheels from sticking out under the mudguards.

Rim offset?
Aah, yes, sorry - going a bit too fast here:
Offset is how much the wheel mounting pad is away from the wheel's center-line. In short, this is what makes the wheel stick further out from under the mudguard - negative offset or how much it will disappear into the wheel opening - positive offset. Zero offset will keep the mounting-pad right in the centerline of the wheel.
Those deep-dish rims are very negative offset…


Let us say you buy wheels that is 25mm (one inch) wider than standard it means that this wheel (if it has the same offset as the factory wheel) will ad 12mm to the inside and outside. While this is not extreme, it just might jam against some inner fenderwell or suspension parts so what you want is a wheel with all the extra width to the outside of the vehicle - you then would need to ad the 12mm to the wheel offset adding negative offset.
If you have the inner room but need to keep your tires inside the fenders, you need to distract the 12mm and get a more positive offset...

Some notes: If you create a too big negative offset it will affect the steering's scrub-radius, ad extra leverage against steering components and ad strain to your wheel bearings so stay conservative in what you do or be real on the negatives you might ad to your truck.

  • Mud Terrian

    Probably the most versatile tire tread: The Mud terrain or M/T. While it states only "mud" in the name, these tires can work very well on rocks and sand under higher powered vehicles. Though they probably fall in the 30/70 asphalt/ dirt range these tires have very little problems doing duty as day to day tire and the tread patterns with a bit more sipes even work great in the snow. These tires have grown in popularity as more users discover that the compromises on the road is well worth the extra traction offroad.
  • Extreme Terrian

    Extreme Tires are what they say; Meant for extreme terrain. This will put them in the 10/90 tar/offroad range or go as far as being "offroad only". These tires are intended for very specific terrain, be it paddled dune tires or chevron patterned mud monsters. They are best used for competition use but find their way to show use on polished show rigs too. One thing is sure - they do not like asphalt! You find these in very large sizes and they can weigh quite a bit more than the comparitive size mud tire. These tires demand respect so make sure you know what you buy!
  • All terrian

    The word All Terrain or A/T in short is promising a bit more than the intention might be. The idea is for the tire to be a 50/50 street/trail tire, giving it decent street manners while still up to the task of trail use. Provided the terrain does not get too muddy or slimy. In sand and snow these tires usually work fine and they mostly carry the "mud and snow" or M+S rating. These treads sport decent siping that helps grip snow and hang on to asphalt when it rains. In real terms if you use your 4x4 mostly on-road but do need trail and gravel road durability, this is your ticket.
  • Winter

    Winter tires must be seen as street tires for winter use. The softer rubber compound and mega number of sipes helps this tire grip in icy conditions. A must for a Winter tire is the "Mountain and Snowflake" symbol - this is the proof that your tire is legal in winter on European roads! Bear in mind that these tires wear faster on tar and the handling in temperatures higher than 7 degrees Celcius is at best "mushy"..

  • Street


    Street or S/T tires carry a heavy weight on their shoulders: Promising saloon car handling to SUV owners...Though this might be a bit unfair, it is true that today's sporty SUV's demand a lot from a tire! These tires are designed to look good while carrying the weight of a full size SUV and deliver decent handling and wear. Most are available in larger rim sizes to cater for the more blingy low profile look. Please mind that most of these tires will NOT get you to the end of a muddy trail, but will get you home safe and fast after the polo-match.

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