TrailBadger

Glad I had the factory install our 3.73 as part of our pre-build sheet

Pmedic920

Thanks so much Guys.

I did a little soul searching, and decided to go with 4;56s.
I really hadn't taken into account how much highway driving vs off road. The other thing i wasn't thinking about is "actual" tire height.
This might sound crazy, I drove around they area of Houston that i work in, and found 8 different JKUs rolling on 35s, got out and put a tape on the tires. I got caught twice but explained myself and they were cool with what i was doing. Any way, not one of the 8 rigs even measured 34". Every one fell between 32" and 33 7/8".
8 is a small sample size but I have to assume my pole is fairly accurate, and my 35s will be closer to 33s when mounted and on the ground.
All being said, 4;56 is best for my situation.

I placed the order today, and I'll repeat, If you're thinking about buying gears w/rebuild kits, I couldn't find a better deal than the one in our Vendor area here on the forum. I have no clue how the customer service is but the price was right. Hopefully it all works out well.

SoK66

I was able to get both gear sets (Yukon) & master install kits from Northridge for right at $500. There's really not much savings going with just the basic kits. Shop your install and you'll discover wildly varying estimates. Places that specialize will almost always be less expensive. If you have no better alternative Four Wheel Parts is usually competitive and competent.

resharp001

Maybe they're better up there in Colorado? 4WP is about as least competent around in my area. I'd think that Houston would have some quality specialty shops.

I warn a lot of people about this....but since you're not likely to find a shop right there on Lake Livingston, be sure you mind the breakin procedure for new gears. You're not gonna leave a shop and jump on the interstate to head home. Don't rely on the shop to instruct you.....some do, some don't. Those first few heat cycles are the most important. Short trips at gentle speeds are ideal, allowing gears to cool in between.

MacRubi2

TrailBadger

Agree, I'd rather locate a quality shop & authorized seller of a product than have joe smoe do the install. I'll spend more green but as you've said I'll feel better knowing it was done right instead of under some share tree. besides I looks for shops that are kept clean. This impresses me without seeing all types of junk around the out edge of the walls. Clean shops means a better and more direct positive attitude.

Wrangeler X

Keep in mind when talking about gear ratio, it's about circumference not tire height. Meaning you need to measure the circumference then find the diameter from there to determine true tire size. The tire squats when on the ground so you can't just measure diameter. All that will tell you is how tall the tire looks.

Mark a line on your tire at the bottom and mark a line in on the pavement in the same spot. Drive the jeep forward until it makes a full rotation and the line on the tire is at the bottom again. Mark that point and measure the distance from line to line on the pavement. That is the circumference. Now calculate diameter.

When you reprogram for gears and tire height use this number.

SoK66

I said if he had no better alternative. Houston isn't your basic Jeeping & off road mecca.

4WP is a good place to start because they probably do more gear swaps than any other outfit. Their estimates are generally reasonable. Good rule of thumb, when you start seeing estimates of $1,000 per axle labor you know to look elsewhere. It's a precise piece of work but if the shop is experinced and has the tools it isn't rocket surgery.

TheDirtman

Most shops that know what they are doing don't want you to bring parts to them. They get the same gears you buy at a deeper discount and it does not save you anything. I know shops that wont do gears if you bring them in or will jack the price because they have had too many problems with people bringing the wrong stuff and the shop has to deal with getting the right parts. Also if you supply parts you leave the warrantee up in the air where you blame a bad install and the installer blames the gears.

Mr.T

Measuring the tire radius loaded, center of axle to the ground has worked for me. As strange as it sounds, both the rolling tire circumference and the static loaded radius change with air pressure and load. And, the rolling tire circumference is equal to the 2pi(static loaded radius). There's a lot of flexing, distortion, and scrubbing aired down.

Here's an online calculator at Kettering.edu that can illustrate this: Tire Data Calculator

• Starting at the top box labeled "Static Data": set Tire 1 and Tire 2 to the same size. For example, let's use 285 for width, 70 for aspect ratio, 17 for rim diameter, 95 for load index and W for speed index.
• Click calculate, Tire 1 and Tire 2 data should be the same in the "Output Spec." box.
• At the "Dynamic Input" box, enter air pressures of 2.5 bar for Tire 1 and 1.25 for Tire 2. For both tires, set the speed to 0 km/h and the and corner weight to 400 kg.
• The only difference in input data between the tires is air pressure. Click re-calculate.
• In the "Output Vehicle Data" box: Tire 1 Rolling Circumference is 2436.3mm and Tire 2 is 2275.2mm. Tire 1 Static Loaded Radius is 387.8mm and Tire 2 is 362.1mm.
• Note that 2pi times the Static Load Radius is equal to the Rolling Circumference, within the rounding error for the number decimal places.
• Note that the difference in section height (rim to ground) for Tire1 and Tire 2 is the same as the difference in Static Load Radius.