My son's 1994 Ranger 4X4 has P215/75 R15 tires on it currently. I'd like to be able to confidently put tires a size or two bigger on it. However, I'm a little nervous about doing so. Based on my perception of the sturdiness of the spindle/brake rotor/4X4 assembly under the front end, I'm not sure it would be the best move to put on bigger tires. I've replaced the front-end bearings a couple times, and frankly, I'm just not impressed with the robustness of this set-up. Can anyone calm my fears about the repercussions of running a larger tire?

 

my father purchased 235/70R15 tires and truck runs well.

 

Really, the trans is probably gonna hate you for it. Unless you are routinely off roading, the bigger tires are more a representation of the drivers ego. Larger tires will strain the diffs, the wheel bearings, the trans, and the brakes.

 

The two main negative aspects of the larger diameter tires is that the "higher" effective gearing will make the engine feel less powerful, and two, the larger diameter tires increase the tire's leverage on the brakes, making the brakes weaker.

You can change the gearing to fix number one (expensive), but number two would be a lot harder to compensate for.

 

What is your axle ratio? A 3.73 ratio and 4.0L 4x4 came from the factory with P265/75R15 tires as an option.

 

The engine is the 4.0 and if I remember correctly the ratio is the 3.73. I am not looking to go to Super Swampers or anything. I just want to go up a size or two to improve the appearance. The truck is a 4x4, but it really doesn't look like it to me with those 215s on there. The present tires are about done, so it's about time to put some on there anyway. Might as well make the change. I appreciate all the comments!!

 

I put 235/75/15 on my '94 2x4 in place of the 225/70/14 it had stock with no negatives at all. Speedo is off a few mph but everything is good.

 

I did about the same thing, I went from puny 215-70-14 to 235-75-15. I had to get centric rings because the wheels (from a newer ranger 4x4) hub hole was bigger. It does feel a bit slower but it looks much better, it looked dorky before. The speedo is off by 5mph. Here is some pics before and after

 

I am dealing with a issue now, my son just bought a 94 4x4 5speed 4cyl for a college car so he doesn't have to drive his 77 150. our proble is it has 31 10.50 on it and it has a very hard time keeping it at 65mph, I am going back to 215/75 -15 on it

 

Because the speedometer is probably reading 8-10mph slow with the big tires, the odometer is probably 10-12% slow too giving you the impression of crappy MPGs too.
The 31s will take a lot more power to roll down the road so power and mpgs WILL suffer.
Try going to 235-75-15s........A middle ground.

 

I went from a 215/75-15 to a 30/9.50-15 and wish I'd done it years ago, I have 3.73s and 220,000 miles on the old 2.9 and it drives so much better with the bigger tires with no power difference. I have never had to replace the wheel bearings just re greased them.

 

The problem I've had for the last several years is trying to find 235/75/15 tires anywhere...everyone's into the big wheels and tires...supply drops as demand drops.

 

You guys all going for bigger tires and here I went smaller on my 2001 Ranger. Ditche the crappy style wheels it came with and went half inch narrower steelies off a Marquis. Had 225/70/15 tires, now I have 205/75/15s and the truck feels much better. Those 225s were too big. Look how nice the steelies are:


Old wheels and tires on left:

 

Actually got $140 for the old tires and wheels, which were pretty rusty in the lip that holds water.

 

255/70-R15 vs 235/75-R15 Tire Comparison - Tire Size Calculator

This site will give you EXACT differences in diameter and MPH, and customizable.