Help cheby guy touched my car.....urgent

[JoeM29]

ok maybe its not too urgent but, i had a friend of the family who was very confident that he could change my gears, ok well this guy didnt look like he knew what he was doing, i dont think he had any tool to measure backlash, looking at the richmond instrustions and using that contact paste, it seems to be hitting in the right spot, is there any way i can make sure these wont blow up the first time i take the car out, for a side not atleast he torked the bolts,
thanks, joe

[6 packin]

Man I feel for ya
All jokes, all rear ends setup in similar fashion. The most 2 important things beinf pinion depth and backlash. Backlash is set fairly easy on mopar rearends. That being said, pinion depth is critiacl, and the first thing you do and set. Like building a house, if the foundation isnt right, whats it matter how the structure is built. in other words it needs to be set to spec, guessing wont do it, can the guy eyeball .005 inchs? I have set alot of 8 3/4 up without tools, just swaping in posi's, mainly keeping the pinion and gear with the same case, by doing that you keep the factory pinion depth and settings, all is left is backlash. I wouldnt want to dust a $200 set of gears because, of inproper setup MOP. Richmound gears are diff from the factory gears, softer, and requires diff setup. I would go back through it and do it right. I think that a dial indicator and magnetic base can be had for under $60, probably the same price to have it setup by a expert. Your choice, but do it right..........tell him its not a Chevy, its a Mopar and they will hold togather for more than 50 miles!

[dartswinger74]

I may be nuts but if the contact pattern is correct I wouldnt worry about it. I have swapped a few used gearsets in 8.25 and 9.25 chrysler rearends just by looking at the contact pattern.

I also had a chebby guy tell me once to put a sheet of paper between the ring and pinion and see if it cut the paper. Something about how it cut would tell you if th gears were set up ok. Sounded dumb to me so I never tried it.

[6 packin]

I know from experiance that the Richmond series gears will Howl like the wind if there not even close, and they still do, even when there right! I wouldnt be as much worried to about the proper backlash as the pinion depth.

[1972roadrunner]

Originally posted by 6 packin
I know from experiance that the Richmond series gears will Howl like the wind if there not even close, and they still do, even when there right! I wouldnt be as much worried to about the proper backlash as the pinion depth.

thats how my 4:10's richmonds were before i corrected the backlash and pinion depth. for some reason, the entire freakin pinion was loose! . got it taken care of though, now i just have to get the motor goin to i can see how the rear end acts now that it's set up properly.

BTW: i built my own tool using a 1/8" thick piece of steel with some bolts with ground off threads pounded into a couple of holes that matched the holes in the bearing adjusters. i then welded the bolts with a TIG, and ground the backside flush (worked great!) to adjust the side bearing caps, and used a magnetic based dial indicator (at college) and followed the instructions in a giant book that has all rear end specs and procedures... i wish i kept the tool or at least got a picture of it...it's hard to explain...

good luck man!

[dave571]

Get a dial indicator and check the back lash.

If it's good, check the pattern. If it's good then you're probably ok. Make sure it's good on both sides of the gear.

You should also check with the guy, about what he ended up with, for rotating torque on the pinion, after he set the preload. This is checked prior to putting the crown gear in.

If he doesn't know what you're talking about, get someone who knows what they're doing to help you, and start over. The rotating torque should be something like 8 to 20 inch pounds(that's what I remember off hand, the spec may vary a bit from that)

If in doubt, find a local gear shop and pay them to do it. I know at my shop, it would cost about 4 hours labour to do the whole R&R. That should give you an idea of the costs.(A lot less than the cost of the gears, or the cost of a car if it piles up on you, while driving)

FYI a lot of pro's don't even do thier own differentials, so don't feel bad about not knowing how to.

[pishta]

how do you all measure 8-20 inch/lbs? My 1/4 inch/lb torque wrench only goes down to 20, and I still dont think it is correct way down there. it is a micromerter style clicker. seems you would have to have a beam type to measure that low of a torque or a hanging scale attached to a known length of wrench. Remember to break a new diff in too! Like a new set of rings, you gotta run it a few minutes, cool it, run it, check it etc. I think Randy's has a good procedure for this on the site.

[dave571]

Check it with a beam style, inch pound torque wrench.

Like I said, The spec might be a little more than that, not much though.

It's not even important that the spec is bang on. It's important that he knows what you mean, and has an idea(even from hand feel) how tight it was.

If he didn't even check, and just pounded the pinion nut up until the pinion stopped flopping around, then you're in trouble.

[1972roadrunner]

Originally posted by pishta
how do you all measure 8-20 inch/lbs? My 1/4 inch/lb torque wrench only goes down to 20, and I still dont think it is correct way down there.

there is a drag torque checking tool, but it's kind of expensive. there is only one of em at my college because of the price. but they do work pretty good - easy to read and use! my pinion has 20"lbs of drag torque on it. i think the spec went from 10 to 25, but not certain. somewhere in that range.

[creative1]

i bought a dial indicator with magnetic base on ebay for $32, shipping included. 1" range. no, it isnt brown and sharpe or starrett, but it will get the job done. lots of choices there, from just the head to complete sets. just figure out what you need and are willing to pay before you buy. it doesnt do any good to get a dial indicator that has a .5" range to measure cam lobes, unless you have a good FLAT surface and gage blocks.