Help With Pinion Nut Torque

[threewood]

Hi all, hopefully someone can help me with this. I replaced my pinion seal as the original was still in place and leaking (1962 Plymouth Belvedere, 318 2bbl, 727) and am confused on nut torque. I found a similar question with a search but it muddied the water even more.

First off, I believe the rear end has been swapped in the past as it is casting# 2070741 which makes it an 8-3/4" correct? I always believed it was an 8-1/4".

Service manual calls for 240ft/lb min. but I have been seeing everyone online talk about preload and turning load, marking the nut, crush sleeve, etc.. The service manual doesn't give info for in-vehicle replacement only for full take down.

Do I just torque it to 240ft/lbs?
What is the turning load?

And because everyone loves pictures...


While I await any clarifications, I'll be busy swapping out the U-Joint (which also looks original)

 

[Cranky]

Yup, 8 3/4 and no crush sleeve in the 741 or the 742....just the 489 unit so there's no chance of crushing any crush sleeve. I generally don't worry about getting that much torque on the nut but I do use some Loc-tite on the threads. Never had a problem in the 30+ years I've been working on them. Got a good impact and a way to lock down the yoke? Some people use a very large pipe wrench to hold it in place but I don't like doing that myself. Another way is to strap in a pipe that's as close to the size of the u-joint bearings as possible. I machined a bar that fits the yoke for when I work on them in the car.....

 

[Hemi Rebel]

Ive never had dealings with a 741 case before. Does it use a crush sleeve? If not then 240ft lbs. If it does, I would tighten the nut a wee little bit at a time till I got about 15 inch lbs of turning torque on used bearings. 25 in lbs on new bearings

 

[62MAX]

If all you are doing is replacing the "original" and you are sure it's never been apart,tighten it to 240 ft/lb and it will be where it was when new.Also,741 case is correct for 1962 model year,even /6 had 741 case.

 

[threewood]

If all you are doing is replacing the "original" and you are sure it's never been apart,tighten it to 240 ft/lb and it will be where it was when new.Also,741 case is correct for 1962 model year,even /6 had 741 case.

Good to know that it is correct for the car. I am pretty sure it has never been apart, considering the lack of maintenance on the rest of the car. The original pinion seal has the DPDC stamp on it and if it had ever been apart a good mechanic would have replaced it. It had been leaking for so long the entire rear end was covered in a dried grease/dirt layer 1/4" thick.


Thanks for the help gentlemen!

 

[threewood]

Final question, hopefully. After the nut is torqued, how much force is generally necessary to turn the yoke? I torqued it down close to spec and it was really tough to turn with a breaker bar so I backed it down to where it turned with force but nothing excessive. Thanks.

 

[Cranky]

Final question, hopefully. After the nut is torqued, how much force is generally necessary to turn the yoke? I torqued it down close to spec and it was really tough to turn with a breaker bar so I backed it down to where it turned with force but nothing excessive. Thanks.

Are the drums still on the car and possibly dragging? Did take out the front bearing and possibly dropped a shim? How hard was it to turn before you took it apart? Like the previous posted said, if you put it back like it came apart, it should turn like it did before.

 

[69Bee]

From the pics, it looks like all he did was replace the seal. Torque to 240 FT/LBS and call it a day. The extra drag you feel is axles, carrier, drums, shoes, etc.. The turning torque is measured when just the pinion is in place without the carrier. Torque to 240 FT/LBS, and call it a day.

ps.. replace the U-joint like you said.

 

[threewood]

From the pics, it looks like all he did was replace the seal. Torque to 240 FT/LBS and call it a day. The extra drag you feel is axles, carrier, drums, shoes, etc.. The turning torque is measured when just the pinion is in place without the carrier. Torque to 240 FT/LBS, and call it a day.

ps.. replace the U-joint like you said.

Sounds good. There is slight drag from the brakes but doesn't seem to affect turning force. Yes, all I did was remove u-joint, removed yoke nut/washer, pulled yoke, replaced seal, cleaned yoke, reinstalled. Nothing else came out.New U-joint is in place, just need to bolt it onto the yoke.

 

[daredevil]

240 dry or 240 with moly lube. Seems like it would make a hell of a difference.I,d go 240 with 30wt and see how it felt.

 

[Cranky]

How many here have a torque wrench that goes that high?

 

[66chargerpat]

@ Cranky, I had to use my machines friend of mine torque wrench. We also held it still in his press. I running a741. It also has the stock solid spacer sleeve, not a crush sleeve.

 

[Hemi Rebel]

Final question, hopefully. After the nut is torqued, how much force is generally necessary to turn the yoke? I torqued it down close to spec and it was really tough to turn with a breaker bar so I backed it down to where it turned with force but nothing excessive. Thanks.

This sounds ugly to be honest. If you encounter resistance with a breaker bar you have a problem. You should be able to grab the yoke with your hand and turn it.

 

[threewood]

Well, it's all back together/lubed and seemed to do fine on the road test. No whining or growling up to 60 mph. I torqued it up as close as I could (175 ft/lb plus a bit more, and that was using a jack on the handle). The yoke was tight but I was able to spin it with the drive shaft, couldn't spin it by itself by hand.


Old original seal, it had seen better days...


Old U-Joint, may be original. I have never seen one with a tab to hold the two cups together...

 

[69Bee]

How many here have a torque wrench that goes that high?

I have two, clicker and an electronic one... :icon_tongue:

 

[Meep-Meep]

I max out my 150 lb wrench then get the breaker bar and a jack handle and give it a little more.

 

[bm02tj]

i have one that goes to 600 ft lbs
i use it to torque wheel nuts on my Renegade motorhome garage

 

[451Mopar]

How many here have a torque wrench that goes that high?

I bought a CDI brand (owned by Snap-On) 30-250 ft/lb torque wrench from MSC when they had a 30% off sale. I think it was about $200.
http://www.mscdirect.com/product/details/06228027

Oops, edited link above. I originally had the 150 ft/lb wrench link, now it is to the 250 ft/lb wrench.

Also, have a Raytech pinion holder
http://www.summitracing.com/parts/rat-18002

For doing new gears/bearings, and measuring rotating torque, I have this CDI dial type torque wrench. Also got it from MSC with the 30% off sale.
http://www.mscdirect.com/product/details/53382016

 

[Garys1969RR]

That U Joint looks to be a little big for the driveshaft? Why are the bearing cups sticking out past the side of the D Shaft? Image 14. Mine were always flush with the side of the d shaft.

 

[threewood]

That U Joint looks to be a little big for the driveshaft? Why are the bearing cups sticking out past the side of the D Shaft? Image 14. Mine were always flush with the side of the d shaft.

The cups are taller than the original when looking at them together. I triple checked the part number, MOOG 315G, and it was a direct fit. I measured the yoke I.D. at 2 1/8" and cap diameter at 1.078". Both were same size as original and the clips fit tight inside the yoke. The first one I bought just giving make, model, engine, etc was MOOG 246 and it was too big to fit the yoke. I hope there are no issues.