4.10 gears

Chad H · February 20, 2004

Hey guys,

I am fixing to put a set of 305's on the hoe and I am thinking of upgrading to 4.10's. Does anybody know a good vendor that I can go thru? I checked Tbryne and he didnt have any on his website. What are ya'll's experiences with switching?

Mule · February 21, 2004

I have 305's on my Yukon. It came with 3:73's and I switched to 4:56. More than one shop said going to 4:10 was not worth the money (too little difference). With the 4:56s and 305's at 65 MPH it is only about 200 RPM higher, but it is back in the sweet spot of the RPM range.

With 3:73s and 305's, my truck was always down shifting and lugging around at too low of an RPM. When I switched to the 4:56, the power was back and the gas milage increased. Just make sure you reprogram your speedo and shift points. If you have overdrive, go with the 4:56s

There is a good chart on www.northern4x4.com that shows RPM with different gears and tires. (http://www.northern4x4.com/cool%20stuff/gear%20chart.htm).

By the way, the 305/70R16 is the same height mounted as the 285/75R16 you have, so if you are happy with what you have now, no need in changing.

Chad H · February 21, 2004

Hey Mule,

Then what size 305 should I get? I got told 305's wouldnt scrub with jacked torsion bars. Thats what I have but I am also installing Ford Keys to give me the ability to lift the front end even more.

Also, what is a good reputable company to buy gears for? I do have to buy two sets correct? 1 for the front and 1 for the back?

Thanks,

Chad

Mule · February 21, 2004

Chad,

I have 305/70R16 BFG Mud Terrains (but I have 6' of lift.) I think 305's only come in one size and only come with the "70" aspect ratio, so if they are all 305/70R16, pick your favorite brand or search on this forum for ideas. It is about 1.5 inches wider than the 285/75r16 and the same height (the 285 has a "75" aspect ratio.) The only place they might hit is in the front air dam while turning, but with a few inches of lift, you should be fine, if your wheel offsets are not too crazy. There is another thread under light duty with a picture of 305s on stock wheels.

The shop that installed my gears used Precision Gear brand, but I don't have a lot of experience in the different brands.

My opinion would be get the tires and see how you like it, because the gear swap is going to be close to $2000 (you need to do two sets on a 4WD). If you swap from 285s to 305s your gearing, performance, RPM, etc. will be nearly identical since the tires are the same height. You wont feel a change with the new tires, and may not feel you need new gears.