Best Pinion Depth Measurement Tool?

[bigred88]

I'm trying to get together all the stuff I need to rebuild a diff, and I've got everything (or already ordered it) except a pinion depth measurement tool. What does everyone here prefer to use? I found this one on summit:
http://www.summitracing.com/parts/rat-10004/overview/
But I've also found a lot of complaining about that type of tool, that it's difficult to get consistent readings.
I've also found universal types for $300 and up. A little more than I'm hoping to spend.

I've also read people saying that any money spent on a pinion depth gauge is money down the drain, and that they've set up 100's of gears and never once used a gauge for pinion depth. But that was on pirate, and this is the first diff I'm attempting to set up, so I think I'll go ahead and drop a few bucks to do it right.

So, anyone have a favorite tool to recommned?

 

[eagle mark]

You only need one for a bare axle housing. If the pinion gear is there it is marked and has spacers. New pinion is marked and add or subtracr spacers.

 

[Blue85]

Why do you want to measure pinion depth? Is there no existing gear set in the axle to baseline from? In the end, the final pinion depth will be set by the gear pattern. The tool is only to get you close.

If there are already gears installed, re-using the old shims is a pretty good starting point. Sometimes you barely need adjustment from there. The shims are mostly to compensate for differences in housings, not gears. The gears are precision machined and the factory already accounted for the housing variations with the original shims.

 

[bigred88]

Well, I've never done gears before so I've been reading just about everything I can find about setting up gears. I had read a few writeups stressing just how important being able to measure pinion depth was. That and the unit repair manual that spent a bit of time outlining the process. Not knowing anything and planning on doing it this weekend, I kind of freaked out and was trying to figure out what tool I could get by the weekend. Then I kept reading, and I read thorough a writeup on pirate that explained everything about measuring pinion depth a lot more, and explained it's role in getting a good pattern on the gears, and why it really isn't necessary if you have a baseline to go off of. That made me feel better about not needing to measure it (actually, Eagle Mark the same pdf you posted was what I was reading on pirate). Your comments do, too. I think I understand why it isn't super important, now.

I just want to make sure I get this right, there's a chance I might be moving cross country in less than two weeks, towing a car, and this is my first time setting up gears with no one other than the internet to teach me, so there's a bit of stress involved.

Thanks for the replies!

 

[Blue85]

If you have time during the setup, take pictures of the patterns you're getting and have the brotherhood critique them.

Don't forget about the new gear break-in process before you start towing.

 

[bigred88]

Fortunately I'm not putting in new gears, just new bearings (that means no need for the break in stuff, right?). My gears looked good when I pulled the cover the other day. I'll definitely be posting up pics of the pattern for feedback. This place is great.

Thanks!

 

[1BEATK5]

If you are doing bearings only, there should be NO setup or shim changes. Normally I just take a pre and post overhaul backlash check. Your pinion depth won't change and won't need to if you keep your current gears. Just check the backlash, change the bearings, then check the backlash to make sure you are in spec. Checking gear pattern on used gears sucks and is really hard to read anyhoo.