Installing new gears, have questions

[Ackattack]

I'm planning on installing new gears (3.73) tommorrow. I've been doing some reading, but still have questions.

First, do I really need a pinion depth gauge? Some people have told me just to use the same shims that are on the current pinion.

I did install a new posi diff before without any problems, but I didn't have to mess with the pinion.

Thanks
Derek

[mplex2000]

I've never tried, it's worth the couple hundred bucks to save the hassle!

[cdowns]

trying to install the gears without even having a overhaul or service manual ??? just take a bic lighter and burn up the dollars save yourself gettin dirty!!!!

[OLDCHEV4X4]

Get a GM shop manual and use marking compound. I never used a depth tool.

[64fleetside]

An option- buy two new pinion bearings, take a Dremel, die grinder ,what have you to the inside race of one- bore it out until it slides on/off pinion. you now have homeboy pinion checker. Set up gears as manual states, use marking compound, using the slide-on bearing, when correct pinion shim is selected, disassemble & press other bearing on pinion. If using GM gears, most of the time the original size pinion shim will be close or right on. brian

[Ackattack]

Originally Posted by 64fleetside

An option- buy two new pinion bearings, take a Dremel, die grinder ,what have you to the inside race of one- bore it out until it slides on/off pinion. you now have homeboy pinion checker. Set up gears as manual states, use marking compound, using the slide-on bearing, when correct pinion shim is selected, disassemble & press other bearing on pinion. If using GM gears, most of the time the original size pinion shim will be close or right on. brian

good idea! I actually have an extra pinion bearing from when I installed the pose.

[LONGHAIR]

I should have saved a copy of my typical response to this to save the typing.............

Don't do it. It is not worth the time and frustration for a one-time thing. It takes a considerable about of skill/practice/patience. The job is only marginally easier with experience because the steps are the same. The only thing experience gains you is a better quess as to the amount of shim needed when you have to change them.
A way to measure the pinion depth really is helpful. It takes a lot of the quesswork out of the shimming. If you "know" that the pinion is right, all you need to do is get the backlash and then the preload. This takes quite a bit if effort and patience. It will be apart and back together several times in this process.
If it is not right, it will self-destruct rather quickly. This sends tons of metal particles through the bearings, requiring replacement again. The expense of destroying all of these parts far exceeds the labor cost. You should get some kind of warranty if you pay to have it done. If you ruin it by doing it yourself....you are buying new parts and still paying someone to do it.

[Psycho71]

I was faced with the same dilema. I did my own. I race slot cars and figured that if I can setup a metal pinion to plastic spur gear on a motor that turns 70,000-100,000rpm, I could do this. It took me about four hours. I did use a dial indicator. no pinion depth guage. I was using stock gears (no marked pinion depth measurement), already mounted to a carrier, installed in new housing. It is a tedious process. As stated before, it will come apart and go together many times before you get it right. I did see where experience would have paid off greatly in knowing the shim size to change wear pattern. I really wish I would have thought about grinding out the inside of the old pinion bearings, that would have been so much easier than fighting the bearing off/on while trying not to screw it up. I had never worked on the inside of a rear end in my life. Mine doesn't make a bit of noise now. After a few break-in periods it has made a couple of trips to the lake w/the boat, and is doing fine so far. Only time will tell.

I can't tell you to do it, or not. If you do, go to every manufacturers website (Richmond,Yukon,Auburn,Motive Gear, Etc.) and print out their instructions. Read them all. Notice the similarities in what to look for. And look for gaps in procedures on one set, in another set of instructions. It's not really that hard, just takes alot of patients and a comfortable place to work on it (table). I don't know that I would do it under the truck, maybe with the bearing grinding trick though. And having someone to help instaliing and removing the differential is also helpful. Holding both bearing races on and trying to drop it in the housing with .010" preload really requires three hands. I did it a few times myself, but a buddy stopped by and the extra hands made it much easier.


Good luck, let us know what happens.
Jay

[wolfthing2000]

that is hone the OLD bearings out for trial fits. Do same for carrier bearings. That needs preload and lash shimming.. You can find good info online and there should be a pamphlet that comes with the gears showing the process.
I am a machinist, have been for over 35 years and I will tell you there is no real secret, justn lotsa patience. Make up charts and record every change you make and refer to it before changing to the next combination or you will be working confused. Sort the shims on scratch paper marked with the size and spread out where you can keep em in their place . Makes it all so much easier. Also keep it all very, very, very clean. I have done it under vehicles. Just spread out some good clean floor cover, I use a big cardboard box spread out.. Another trick I use for Pinion Pre-load when you don't have a in/.lb torque wrench is put a bar through the yoke, mark it at 12" and hang whatever fraction of a Budweiser can of water off the bar at 12" with some wire. ( ie: 1 full bud of water = 12 in lbs. or 1/2 bud is 6 inch lbs)

[incoma]

I bought a video from randy's ring and pinion. The video was from richmond gears, and convinced me that it was too much of a job without the correct tools. Naturally, some will perform the job without the tools and get lucky. I wasn't willing to burn up my new posi unit, gears, axles, etc. Save a $ now, pay a $ later if it isn't installed correctly.

[Fastfun]

I paid $250.00 to have mine set up last year and it was worth not having the hassel or worry of it failing in BFE. Just my opion

[Ackattack]

Well the gears are in. I finally got it all put back together last night (getting the bearing pressed on delayed me 2 days). I took it out for a spin last night, and I couldn't hear a thing from the rearend. Set the back lash at .006". My gears said to set it at .008" +/- .002", so I should be good there.

I took it out on the highway and these gears seem to put the engine right at the sweet spot (about 1900 RPMs) while doing about 60.

I have a few more things to do. I'm getting a vibration at about 30 mph, so I'm going to check that my drive shafts are aligned correctly...probably 1 tooth off. And then I have to install the drive gear for the speedo when it gets here.

Overall it was a pain to do, and I definatly understand why people pay others to do it. I don't know if I would do it again. But I did it, learned some things, and life goes on.

[TugOwar]

congratulations!