U-joint question

[carrman]

After having a little email exchange with the one and only Krautmaster, he informed me I have 7260 u-joints in my Newport. I'm going to have Dr. Diff build me a 3.23 with a Sure Trac II center section. He only has either 1350 or 7290 yokes for the diffs her builds. Would it behoove me to have a new driveline built for 7290 or 1350 u-joints, or should I just get a conversion joint for the new diff and call it a day?

 

[CBODY67]

Not knowing of your ultimate intentions, if you have a good driveshaft with no vibrations, then the conversion joint would be the easiest thing to do. One without grease provisions in it. Reason for that last item?

Many OEM u-joints used to be the solid type with no grease fittings and were retained with a thin bead of "plastic glue" on the caps when they were installed at the factory. So when they were changed, they were usually replaced with the ones with "better" grease fitting in them and clips to hold them in.. Which means that you did not have to disassemble everything in order to grease the end caps, as time progressed. BUT in the drag racing arena, if you needed ultimate strength, you got the "better" joints with a solid center section, not drilled, and checked for grease prior to installation.

Now, my late machine shop operative and former drag racer related those facts to me many years ago, but I don't know if there might be any information of how much more torque the drilled joint will endure compared to the solid ones. FWIW.

Just some thoughts,
CBODY67

 

[carrman]

Not wanting to race it, she’s just used as a cruiser. But there will be times of spirited acceleration when entering the freeway

 

[70bigblockdodge]

I have been pounding the dogpee out of a homemade driveshaft with 7260s in it for 13k miles behind a 4speed. Most of the problem regarding strength is in the 1/4" 28 bolts that hold the straps on the rear yoke. I have not had that fail on above driveshaft but when I went to change u joint at the rear of the driveshaft in June before I drove it to South Carolina the new caps would push in by hand, clips were the only thing holding them in. So I promptly tacked them into place with evenly spaced welds and drove it the rest of the year. Winter project is to get a new driveshaft made with 1350s because I'm putting everything on the same rear joint/yoke so I can swap centers between all my cars. Nothing wrong with 7290s just more $$ and not as readily available as 1350s. You could just use conversion joint till driveshaft loosens up the yoke holes then build one.