so i was talkin to the guy that would help me do my rear end, i dont know if yall remember i have 3.55 NLS and i want maybe a 3.73 or 4.10 LS for my 2002 f150 4.6

anyways, he said its not hard to do, but the only thing is the bearings have to be spaced out enough....and if they arent the rear end may whine. ok if this is true how do i know how far to space them out, and would, for gas milage, it be better to go with 3.73 or 4.10. i haul a pretty good load of stuff from time to time and with the rear end i have now its kinda hard to get up to speed

 

Get at LEAST 4.10's, otherwise it's not worth the money to do the swap.

Changing gears is just as much an art as it is skill. It takes a lot of patience and fiddling to get everything just so.

 

X2
Going from 3.55 to 3.73 you probably wont even be able to tell the difference.
Put the 4.10s in and you'll love it!

Phil

 

alright!!!! so what about the bearing whine if its not spaced out properly? how do i figure out how to space them to where they dont whine,

 

In my honest opinion, If you've never done it before. The best way to get them just right is to pay a pro to install them!

Phil

 

thats the thing tho, theres not any "pro" i can take it to around here, my buddys dad said he could do it, but its kinda ehhhh

 

If he has the tools and more importantly, the EXPERIENCE, it may work out fine.

 

I understand,,you got do what ya gotta do. Hopefully he has done it before,,if so you should be ok.
I'm not familiar with Pittsburg Texas but if you have a 4X4 shop or tranny shop or even a dealer could do it.
I saw a step by step on the net but I cant seem to find it for you.

Phil

 

haha theres not much around in pittsuburg or anywhere close, and i dont really know if i wanna drive a hour and a half to get it done, ill talk to him some more until he builds m confidence a little more!

 

The "spacing" he is referring to means the contact pattern/backlash setting on the ring and pinion gears. If not set properly, it will whine.

 

yea hopefully he dosen't mean "space the bearings properly".

If he is really talking about spacing bearings I wouldn't let him do it.

gear swap write up

 

Actually, the "spacing" is done by adding, or removing shims that are behind the pinion bearing and carrier bearing races. Ford has special tools for the pinion depth shim, but the backlash is adjusted by "hit or miss". Put it together, measure, and adjust if you must to set the correct backlash.

 

Richmond Gear sells a video through Summit Racing that is good information on how to install rear gears and set them up. Cost less than $20 last time I looked. You might could do it yourself if you are a fairly experience mechanic and you study what you are doing well before taking it on. I disassembled one rear and replaced defective bearings and I switched gears in another one. Both had used gears and they would sing just a little afterwards. It's fairly tricky. If you work slow and carefully, you might be able to do it. Crushing the new pinion sleeve is a real bear. It took about 400 ft. lbs. And if you don't get the pinion shim correct the first time, you have to press off the pinion bearing and try again. After you get the pinion shim sized correctly by trial and error, it's fairly easy to get the shims correct on the carrier bearings. To do it correctly, you need a press, dial indicator, and some way of crushing the sleeve. Richmond Gear showed using a huge impact wrench. However, you need to crush it just the correct amount to get the pinion bearing preload just right and they don't show that. You are supposed to use a torque wrench that reads in inch lbs. to correctly measure that. The Richmond Gear gears come marked and if you have the tools to measure the depth from the center of the carrier to the pinion, you will be able to choose the correct pinion shim the first time.
Really, get someone who knows what they are doing.

 

WOW! I now know that I will never be changing my own gears