How to Measure your Trailer's Wheel Bolt Circle Lug or Bolt Pattern
In order to replace a hub on your trailer, you will need to know the bolt pattern or lug pattern. Trailer wheel hub patterns can be defined by the number of bolts or lugs per wheel and the diameter of the circle that the bolts are arranged on. Determining the bolt pattern is rather easy, but it is very important that accurate measurements are taken. The majority of boat trailers on the road have a 4, 5 or 6 lug pattern. A very common designation for boat trailer hubs would be 5 on 4-1/2 or 545 for short. This means that the hub has 5 bolts spaced evenly on a 4-1/2" circle (see 5-lug diagram).
Determining the bolt pattern on your trailer:
- You will need to first count the number of lug bolts on one wheel. Most trailer hubs typically have 4 or 5 lugs per wheel/hub. Heavier duty, higher capacity trailers generally have 6 or 8 Lugs per wheel.
- If the trailer hubs have an even number of bolts holding the wheel, measure from the center of one bolt to the center of the bolt directly opposite using a ruler, tape measure or caliper. The hub lug bolt pattern will be determined by the number of lug bolts and the distance between the opposing hub bolt (see 4-lug hub diagram). All but 5-lug patterns are measured in this manner.
- If your trailer wheel hubs have 5 lug bolts, measuring is slightly different. Choose any lug bolt and measure the distance between the back of one lug to the center of another that is directly across from it. Be sure that you skip one bolt when measuring. You can measure the distance in either direction
The two most common lug patterns are 4 on 4" and 5 on 4-1/2" hubs. These hubs are typically seen on smaller boat and utility trailers.
NOTE: If you are replacing older wheel hubs, wheels, integrated hub/drums or hub/rotors the bearings should be checked for wear and replaced as necessary. Always use a high-temperature wheel bearing grease when re-packing your trailers hubs.
4, 6 and 8 Lug trailer wheel hubs are all measured in the same manner.
If you need to replace your hubs, please see our current selection of boat trailer hubs. We also have a full selection of grease & oil and bearings & seals for all your needs.
Hi, I am restoring a 14 foot boat trailer.
It has 8 inch rims on a single 1 inch axle stud.
I would like to go to 5 stud wheel bub with a 12 or a 14 inch rims tires.
So the trailer will ride higher from the ground, what you recommend. If possible.
The trailer wheels measure 4.5” on a 5 lug. I need an adapter that fits my Jeep 5×5 pattern. Is there anything you would recommend? Thanks
I am looking for a 13" rim for my vintage 1967 Trailblazer camper. The size I am looking for 13", 5-bolt-4.5" with the central hub being 2.5". I have some photos as to what I am looking for. Please let me know if one of your rims would work. Thank You, Timothy
I have a 1986 hydrosport bass boat with a phantom trailer.If I measured correctly my bolt pattern is 5 by 4 and 5 /8
Does this sound right for a boat trailer wheel?
I have a TRAILER with 215 70 r 14
Can i put a new tire and rim
205 70 D15. IT SEEMS THE NEW TIRE AND RIM WILL NOT FIT AND I JUST BOUGHT 3 BRAND NEW TIRE AND RIM WITH NO RECIPTS
WHAT SHOULD I DO