Mopar Action On-line – Tech Questions


Tech Question

Mike Eaton, Minot, Nd, 71 Dodge Charger 318

I Had My Rearend Rebuilt Recently
(489 Casting With richmond 4.10 Gears, Has 10 Spline Yolk And The Big U-joint)
And I have Crosthreaded One Of The Holes That Secures The Strap To The Pinion Yolkand Canot Get A Bolt In Straight. I Would Like To Know If I Canjust Buy A New Pinion Yolk, Torque It To 240 Ft/lb And Call It Good,just Replace Crush Sleve With A Solid Non-crush Sleve With Newyolk And Torque To 240 Ft/lbs, Or Do I Have To Buy A New “crush” Sleveand Have The Patern On The Teeth Set Up Again? Is A Solid Non Crush Sleverecomended On Street Cars? I Am Not Too Familiar With Working On Rear Ends.thanks, Any Help Is Apreciated Greatly

Mike, first of all, I wouldn’t be so quick to pull the yoke off at all. Ithink there’s enough meat there to simply drill it out an Heli-coil it. It’sstandard 1/4″-28 SAE (fine) thread.

Failing that, here’s the basic procedure: You must measure the turningtorque before you pull the yoke. To get anything repeatable, the drums mustbe removed – no big deal. Then you must turn the yoke with a low-rangeinch-pounds torque wrench on the pinion nut and record the reading. Theactual number isn’t important as long as you are confident that it was setcorrectly by the builder. The reason is that now you are reading the turningtorque with the diff and axles in place, which creates quite a bit of ‘drag’.

Now install the new yoke and torque the nut to 170 ft./lbs. Then re-measurethe turning torque. If it’s back to the number your recorded, you’re done.If not, keep tightening the nut in 20 ft./lb. increments until you reach therecorded number, but not tighter than 240 ft./lbs.

If you never reach the target number, simply remove the yoke again, pop outthe pinion seal and front bearing, then slide out the collapsible spacer(sleeve). Install a new spacer, the original bearing (cone and rollerassembly), and a new seal, which should be the same brand as the one youremoved (a different seal would have a different amount of drag, throwingoff your turning-torque readings). Then repeat the procedure in theparagraph above.

Solid spacers are 100% streetable, and greatly simplify this procedure – itthen becomes just a nuts-‘n’-bolts deal, no measuring required – same as a#741 or 742 pig. You could even do this now, but you’d need to mess with theshims to recapture that original turning torque, which would be a helluvahassle with the pig still in the car.



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