hi, everyone

I purchased an 05' f150 recently for a 'real good price' and now obviosly things arent going so well. When i bought the truck the previous owner advised me that there was a slight knock in the rear end and its most likely the rear u-joint. As im no mechanic i believed him and decided that the $25 u joint is gonna be an easy fix. So i bought a new u-joint and tore the rear end down taking out the driveshaft and diff cover off. The stock u-joint was in perfect condition what a surprise but i cant say the same about the diff and the ring and pinion gear. There was excessive wear on the bearings and quite a bit of backlash in the ring gear. At that point i had not looked much into it so i cleaned everything put the whole thing back together and filled it up with oil.
My local ford dealer advised me that i have a ls diff and sold me the friction modifier, i later found out that thats a load of bull so now my rear end is knocking like there is no tomorrow and im looking at a complete rear end rebuild. I was quoted a price of about $3500 for the job so i decided to do it myself.

 

Friction modifier doesn't hurt a non-LS rear. You simply bought a truck with a rear end on its way out.

Why don't you go to the boneyard and get a whole rear axle? That's gotta be a hell of a lot cheaper than any other way, and easier to change. There's a lot of precision work involved with rebuilding a diff.

 

Now down to business. I did a whole bunch of reading on the project at hand and this is what i found out and purchased.

my stock rear end is a 9.75"
gear ratio of 3.55
the diff is an open carrier type

I called the people at west coast differentials the web site is www.differentials.com
and ordered myself a 3.55 ring and pinion gear from us gear a detroit true track defferential and the master install kit which includes all bearings seals shims and races needed for a total of $ 1040 I also bought the machinist dial for measuring backlash a seal and race driver set and a bearing separator kit. I managed to get my hands on the ford shop repair manual for all ford vehicles made in 05' and 06' this is what the mechanics in the dealership use to do the job dont ask me how lol.
As i start the project now i will post pictures and diagrams of the work being done hoping to shine some light on the grey areas of this type of work any input from u guys would be helpfull and i can post diagrams and troubleshooting guides from the ford manual if anyone needs them as they are doing a similar job.

 

I called a couple of places but i was offered prices in the $1000 dollar range and those rear ends had about 150 000 km on them so i figured this is a better option

 

here is a diagram of my rear end

 

does anyone know if switching from an open end diff to a limited slip will cause problems during installation. I was assured by the manufacturer that its a perfect fit and direct bolt up and i wont have to do any kind of modifications

 

I would have took GLCs advice.

 

^^^ X2, especially as you said "I'm no mechanic"....I dare say you will get in 'over your head' in a hurry here. If you do succeed you will love the Tru-Trac unit..it's more that just a ls unit. Word of caution with the tru-trac..ONLY use dino 80-90 gear lube in it, NOT ANYTHING SYNTHETIC !!

 

I was advised about the oil type by the people at west coast differentials i just ordered new rotors and pads for the back and the front and im waiting to get them delivered than i can start since i have to take the rotors off anyways to pull out the axles. I gotta say im pretty excited yea its not gonna be easy but hey im up for the challenge. My boss got his rear end rebuilt 3 time over the last 2 months by the dodge dealership he drives a ram 3500 pretty weak id say but anyways the mechanics there are soooo good they messed it up everytime i kind of wanna see if i can do better its not rocket science its a rear end

 

Hey sam are u running a true trac in ure truck i would like to hear some feedback on the performance of that diff and thanx for the advice on the oil

 

You won't know it's even there, until it is needed for traction, and NO clutches to wear out. One of the best up-grades I have done. Just a note on the re-build...you will have to re-use item #16 (anti-lock ring) on the true-trac

 

So yesterday i finally got down to bussines took the axle off and rebuilt it. I have some pictures to post i will do that shortly. Had some troubles with rusty brake lines and the parking brakes looked terrible but had no time to deal with that yesterday so i left it. Everything seemed to go well put the new races in set the bearing preload on the differential bearings measured the backlash adjusted all good. Setting the pinion depth was a bit grey tho this whole paint thing seems a little old school anyways i thought i had it so i put it all back together and drove the truck to see how it went. Accelaration was fine but as soon as i take my foot of the gas its starts whining as it slows down on coast. it is also leaking out of the pinion seal. I know the seal was installed properly believe me i took my time and used a seal driver it went in perfect nice and square.

 

My opinion is that the pinion shims are not correct also the specs called for only 20 ft lbs for the pinion nut and locktite ok but it took quite a bit of force to get that flange on im thinking could it be too far out causing the pinion to move back and forth.

 

Pinion depth is incorrect.

http://www2.dana.com/pdf/5717.PDF

 

Don't drive it until you get the pinion set up correct or you will ruin the new gears