Truetrac Install
 

Let me preface this with I’ve done zero differential work. Having done a couple blowers, cam swaps and transmission replacements, do you think installing my Truetrac is something I could do myself with the aid of youtube? I have the Truetrac, ring gear spacer, and two sets of carrier shims which was all I was told I need from Eastcoast Gear Supply. Aside from chalking the ring and shimming the carrier to get good wear marks, what else would I need to do? The truck only has 25k miles on it and I’m keeping the stock ring and pinion so I shouldn’t have to work about shimming the pinion or any bearings and seals right?

You won't know until you try. Yank the axles pull out the carrier. Measure the shims on each side of the stock setup and write them down. Then unbolt the ring gear and put it and your spacer on the new carrier. Get the shim setup correct for the new carrier and your done. Playing with the shims is the only part that takes some time. The rest is a cake walk. If you can't get it right then put it back stock. It's that simple. I have faith. You only learn by doing it.

Do I need new carrier bearings to press on the truetrac? I assume I can't just pull the old ones off and reuse them right?

Also how do I tell how tight aka how many shims I need in?

You will need two new carrier bearing. The new carrier should be the same width as the original. The spacer is needed for the gear change setups. You may not need it, now that I think about it. But if ECGS says you need it then listen to them. Once you measure the shims on each side of the carrier add both sides together and that is your total shim required. So if total is .600. You need to have .600 when the left and right shim are added together. I.e. .400 on the left side and .200 on the right. You can change the left and right however you need to in order to get the pattern and backlash correct but total they need to equal .600. Your # will differ but that's the basic point.

OK that makes sense on the carrier bearings. ECGS said that the carrier break is different for 3.08/3.23 which the truetrac is sized for and my 3.42 so I'll need the spacer.

When I slide the axles out of the stock diff, I assume I have to take off the rear calipers, rotors, parking break to get enough room?

Also when I chalk the ring gear after its all assembled, do i just spin it by hand to check for the wear pattern?


What may do me in is I have no idea how to measure backlash nor do I have a dial gauge (this is what its called right?)

Sorry for all the questions and thanks for answering them!

https://m.harborfreight.com/1-inch-t...not%20provided i don't care for harbor freight but this should get you by to check backlash, get a magnetic base like the one in the second picture if it doesn't come with it.

Pull the stock diff out and put in the TT with the shims from the stocker. Go from there.

Preload and backlash setup is more experience than anything else. Watch a few videos on YouTube.

Is it stupid to reuse the axle seals if the truck only has 25k miles on it?

Nope. Reuse them. I did.

Perfect, thanks

Only reason not to is if you think you messed them up by pulling the axles out about 4 inches.

At 25k, that's barely broken in. My 06 still had the stock seals in it when it was rebuilt a couple of months ago at around 193k.

I found out my local Napa rents a dial indicator and they also rent a case spreader. Should I get the case spreader to preload the carrier bearings or just tap in some extra shims? If so how much do I "spread" the case?

don't use a spreader just tap the shims in.

RT

Yep tap them in. Spreader not required.

Oh, ok. In reading how to's some recommended spreading the case to ensure you get enough carrier bearings preload, especially on higher how vehicle to prevent ring gear deflection. With 650-700hp going to it I thought I'd need the extra preload, but looks like I don't!