[jarretts70]

I would like to try to setup my own rear end. I've built motors & transmissions and have rebuilt posi carriers, but never tried a full rear end setup. However, I don't have an inch-pounds torque wrench. The fancy dial style ones are dang expensive....but the beam ones are pretty affordable. My question is are they accurate enough?

Bear in mind I'm not doing it for a living. I might build one rear end every 5 years.....If I have to spend serious $ on a wrench it might be more cost effective to take it to the pros...

The rear in question is a 12 bolt. Bought the stripped hulk of a 71 Grand Prix that was a 455 car. Still had its disc brakes & the 12 bolt. Pulled the rear, popped the cover....and it's a posi. Score! Only paid 600 for the whole car. It has a 3.07 gear which I plan to replace with a 3.42. I'll install new side gears & spider gears, new posi clutches & springs, etc...

[Stripes]

I think if your not reading inch pounds its likely the torque wrench will not be accurate enough to set the preload on the bearing. Sorry. See if you can borrow one.

[djustice]

I am no expert either, but i have done one GM 8.5" complete overhaul with new yukon diff, master bearing kit and reused ring gear.
In the final assembly i used a beam type torque wrench like this: https://www.ebay.co.uk/itm/Gearwrenc...-/392230354132
to set final drag with carrier and ring gear in place to yukon's specs (since i used their parts) and it has worked good for me for about 5 years so far.

[crustysarge]

I have done a handful and am lucky enough to have scored a $$ dial wrench at a USAF excess auction years back. It works well. That said, I have had hit and miss on the whine issue. I don't see why a beam wrench won't do it for you.. If it is out of the car it makes things a lot easier to watch the torque. Not hard. You need a press also. Don't know if this is in your budget but:

https://www.ebay.com/itm/Proto-6169a...wAAOSwb5leoLb0

[RocktimusPryme]

Im actually doing this right now to an 8.75. I had to make my own tool to do the side adjusters. Autozone and others sell a 0-80 inlb needle type torque wrench for like $25. Its usually instock. Or you could look for a nicer one used.

We checked several cheap torque wrenches at work when I worked for general atomics just for fun. Harbor freight and whatnot, all the ones we checked were within spec. If I were going to use it a ton I would buy a better one. For basically single use, buy the $25 one.

https://www.autozone.com/wrenches-pl...nch/752621_0_0

Hell you could probably use it once and take it back and they wouldn't bat an eye. Which I wouldn't suggest with a lot of companies, but the parts stores have sold me an incorrect part enough times that Im not above some shade.

['ol Pinion head]

SnapOn inch lb dial type here, bought it lightly used 25 years ago. Have used it during setup to ck pinion drag on over 800 builds. Before that, the fellow I learned to build rears with used a cheap beam type inch lb. We were getting a few comebacks at the time, but near all were related to the used 3.42's & used 3.73's that we'd pulled out of 1/2 ton vans.

Torque wrenchs can get out of calibration. Have a near 40 year old clicker type ft lb Craftsman torque wrench that I've had recalibrated 3 times since I bought it as a teen. Few years ago, picked up a cheap HF short body clicker type torque wrench. Only bought it as the Craftsman was in for recalibration. The feel just isn't right with the short HF ft/lb torque wrench.

[Tom Vaught]

We had a Snap On Calibrator for Torque Wrenches at my work in the Engine Build Up room. They used check their Snap On Torque Wrenches every 3 months as they were constantly building engines for testing.

I had my Torque Wrenches checked for accuracy in the last year and they were still right on the money at several checking points. I also have a older Beam Type Craftsman Torque Wrench in both 1/2" and 3/8" sizes and a Inch/Lb torque wrench and all read very close to the $$$ torque wrenches I have. Nothing wrong with Beam Torque Wrenches if you can see the needle properly when doing the fasteners.

Tom V.

[RocktimusPryme]

It seems they stay pretty good if you take care of them. On the planes we had to lower the click type ones to their lowest settings for storage. And if you drop one it’s an auto recalibration.

But if you buy a used one you don’t know how it was taken care of.

[AG]

I use the beam deflector type (in lb) and it has worked great, no issues. Never had to take arear I built apart and fix it. Need to check it with out the posi in place. I'd recommend taking the posi out of your 3.07 and checking that pinion pre-load to get a feel first. A new crush collar will be higher at around 22-24 in lb.

[Ben M.]

Originally Posted by RocktimusPryme

It seems they stay pretty good if you take care of them. On the planes we had to lower the click type ones to their lowest settings for storage. And if you drop one it’s an auto recalibration.

But if you buy a used one you don’t know how it was taken care of.

Exactly. SRR showed me how to store them 15+ years ago and I've done it ever since. All but the junkiest no-name wrenches seem to hold their torque settings pretty close if you store them right and aren't using them every day multiple times.

I use the needle deflector style that my dad bought in high school 50 years ago for the smaller jobs like lash and pre-load on steering boxes.

[mrennie]

Originally Posted by djustice

In the final assembly i used a beam type torque wrench like this: https://www.ebay.co.uk/itm/Gearwrenc...-/392230354132
to set final drag with carrier and ring gear in place to yukon's specs (since i used their parts) and it has worked good for me for about 5 years so far.

I have the same torque wrench but mine is older and says K-D on it instead of Gearwrench.

Worked great to set pinion preload, find drag checks, and also very helpful when I rebuilt my steering box and had to set the "over centre" preload for the pitman shaft.

Price is affordable, technology is proven and accuracy is sufficient for the task. (some listings say +/- 4%, some say +/- 7%)

I keep mine in the original shipping box and while I have only used it 5 times, its there when I need it.

One point of interest, mine came with pointer not centered on scale...meaning is was at 2 inch pounds instead of 0...so for all my measurements when pulling in that direction, I added 2 inch pounds. If I was going the other way I would have deducted 2.

While you are ordering, don't forget you will also need a 1/4"F to 3/8"M adapter and a 3/8"F to 1/2"M adapter to get from the 1/4" drive of the wrench to the 1/2" drive of the socket on pinion nut.

[Formulajones]

I use a very similar wrench that Djustice posted, and have used it for many many years setting pinion preload. Works perfect

matter of fact I prefer the beam style over a clicker for this type of operation. Clickers aren't that accurate for this type of deal.

Generally it takes a little more effort to get them moving and then the torque required will level off, but the clicker will just click and that's it, you don't get a "real" reading with it during rotation.

Technically once it's moving, you should be pulling nice and slow/steady and watch the beam to get a correct reading.

[mjc34]

Silly as it sounds, on my second build, I used a 6" coffee can and a fish scale. Worked perfect. Had a pricey snap on inch pound dial indicator for the first build. The can works better.

https://www.flickr.com/photos/782227...7648583763511/

https://www.flickr.com/photos/782227...7648583763511/

['ol Pinion head]

I'll stick with my trusty 1/4" drive inch/lb SnapOn dial type which has never been dropped on anything! After I use it, it gets wiped down & put back in its case, not laid on the bench or top of the tool cart. Pinion drag.... looking at 12-14 inch lbs w used bearings/races. 22-24 with new bearing/races, fairly small measurements.

Have had a few beam type torque wrenches in my hands that had a plastic pointer on the end that moved around, hard to read & gave bad readings. Have also had a once decent Craftsman 1/2" drive beam type ft/lb torque wrench that the metal rod/pointer had to be tweaked to zero out. Something i could trust in a pinch torquing, say lug nuts on alums wheels, but not assembling an engine.

[Schurkey]

Originally Posted by Tom Vaught

I also have a older Beam Type Craftsman Torque Wrench in both 1/2" and 3/8" sizes and a Inch/Lb torque wrench and all read very close to the $$$ torque wrenches I have. Nothing wrong with Beam Torque Wrenches if you can see the needle properly when doing the fasteners.

I agree--and disagree.

A properly-made deflecting-beam torque wrench is simple, inexpensive, reliable, and accurate when used properly. It is absolutely NOT fool-proof.
They're subject to parallax error when not looking "straight down" at the needle/scale.
They tend to not have a ratchet head; so they're a pain in the ass to use.
They need to be held so that the handle "floats" on the pivot. If the handle doesn't pivot, they're less accurate.
Because you have to see the scale, and have proper hand position, and hold the torque long enough to "see" a stable reading--holy crap they're an ergonomic nightmare.

The shortest possible story is that the tool is very simple, which directly leads to it being NOT simple to use. It's analogous to saying "Here's a hammer, here's a chisel. Go carve that block of marble into a beautiful sculpture."

Originally Posted by mrennie

One point of interest, mine came with pointer not centered on scale...meaning is was at 2 inch pounds instead of 0...so for all my measurements when pulling in that direction, I added 2 inch pounds. If I was going the other way I would have deducted 2.

Grab the indicator needle, pull it 3 inch-pounds the other way. Keep tugging until it reads "0" when you let go.

Originally Posted by 'ol Pinion head

Have also had a once decent Craftsman 1/2" drive beam type ft/lb torque wrench that the metal rod/pointer had to be tweaked to zero out. Something i could trust in a pinch torquing, say lug nuts on alums wheels, but not assembling an engine.

IF (big IF) the deflecting-beam torque wrench is quality-made and used properly, they're every bit as accurate and repeatable as the expensive ones. ALL the problems come from "operator error".

When I used to torque head bolts with my Craftsman 1/2" deflecting beam, by the time I got to the end, my arm was shaking so bad it was impossible to see what the reading was. Changing to a properly-calibrated, properly-made micrometer-adjusting clicker solved all the problems inherent in the beam type EXCEPT for jobs that require TESTING torque instead of ACHIEVING torque. It did create two new problems--remembering to return the setting to the lowest torque stamped-into the micrometer scale after each use, and having to occasionally have the calibration checked/corrected.

Deflecting-beam and dial-type torque wrenches excel at testing torque.
Micrometer-adjusting, split-beam, and typical "electronic" wrenches excel at achieving torque.

For the record, the two companies I've used to service torque wrenches charge DOUBLE or more, for servicing electronic torque wrenches compared to "clickers".

[jarretts70]

I've been searching for a good used dial one for years, with no luck. I can buy a beam one like the gearwrench for about 65, so I'm going to give it a try.

[jarretts70]

Also the coffee can fish scale idea is brilliant....

[jarretts70]

Related but slightly different topic..My rebuild plans are circling the drain.

Holy cow are parts expensive to rebuild this thing. 500 Canadian just for a side/spider gear kit. 258 for posi clutches. And so on. Stupid Canadian dollar...I can get a whole new Eaton posi carrier for 830.

The existing side gears & spider gears look fine. No abnormal wear on the teeth. The splines look good but there is definitely some free play between the gears & axles. Plus I read somewhere on the internet that OEM side gears aren't the strongest (internet is always right, right?). Hence my plan to replace them. But unless I find more cost effective parts I don't think it's worth it. I'll just clean it up & sell it. Opinions on the quality of OEM gears?

[lust4speed]

It's not exactly brain surgery. A beam wrench is more than adequate and a clicker wrench would be terrible. My old Pontiac mechanic friend that has since passed set them up by feel, and once you twist one set up correctly it's easy to remember the resistance.

[Schurkey]

Originally Posted by jarretts70

I've been searching for a good used dial one for years, with no luck. I can buy a beam one like the gearwrench for about 65, so I'm going to give it a try.

$65 seems high, even if it's Canadian dollars.

They'll all be Chinese; I don't expect any other option. Taiwan if you're lucky.

https://www.amazon.com/Neiko-03727A-..._t1_B0742LPSDX

Under $25 in the USA. More, I suppose, North of the border.

Originally Posted by jarretts70

The existing side gears & spider gears look fine. No abnormal wear on the teeth. The splines look good but there is definitely some free play between the gears & axles. Plus I read somewhere on the internet that OEM side gears aren't the strongest (internet is always right, right?). Hence my plan to replace them. But unless I find more cost effective parts I don't think it's worth it. I'll just clean it up & sell it. Opinions on the quality of OEM gears?

Have you tried it? Does it NEED to be rebuilt?