I'm having trouble keeping the drive shaft in my 74 Charger. I've broke 2 U-joints, a pinion yoke and dinked 2 factory drive shafts. There's no inherent drive line problems with the car other than lots of torque moving a heavy car.

What's my best option for a stronger drive shaft that's not going to break my piggy bank? Aftermarket? Custom made at a drive shaft shop? Also, who's a good vendor/brand for stronger U-joints?

Tell us about the power you are putting to the ground ? Slicks ? Dana ?

What size u joints are you running ?

440/4sp, 415 hp., 500 fp. torque at the flywheel with regular ethanol gas. 8 3/4 rear with 3.23:1 gears, Stock NAPA U-joints, 8 inch wide Goodyear GT street tires and a dual disc McLeod RST clutch. It's basically a stock setup with a warmed over 440.
I don't rev it and dump the clutch, but I do like to drive it hard.

Are you using solid U joints? the kind with no zerk fitting or lube passageways drilled in it?

I never broke a U joint with my 64 300, similar build but a warmed 413 and wider tires compared to your build. I did rip the ear of the yoke on the rear end though, but that was with the 4.10 gears I put in place of the 3.23's it had.

My U-joints have the zerk fittings. Who sells the solid type? I'm guessing the solid type are maintenance free or do they need repacking at some point?

Depends on if you have the small or large U joints, Rock auto shows several vendors for the smaller one.

Spicer 5811X seems to be the only option for the larger one at RA.

Large U-joint, Thanks for the part# Supercuda.
I had, briefly, the large/small adaptor U-joint to make use of a sure grip pumpkin I have and it broke during the first test drive after doing my 4sp swap.

gotta be something wrong with your drive line angles. I had a '74 Challenger, 440/4spd, 8 3/4 SS springs the car runs 11.7's all day with stock small u-joint driveshaft, small in the front, crossover u-joint in the back. I broke axles and rears before, but never a u-joint.


are you sure everything is lined up correctly?

watch this,

https://www.youtube.com/watch?v=gmV4qwLfOMY

I replaced the engine and trans mounts less than 1K miles ago. The axel could be wrapping up. I have the stock pinion snubber, maybe an adjustable one would help.

gotta be something wrong with your drive line angles

X2

What's in it for springs and shocks?

It's all stock with new shocks. 73 & 74 leaf springs also have a oval shaped rubber bushing on the forward spring mount.
I think I need the 1971 springs with the conventional round rubber mount. I'll have to change axel perch also as they are different.
The 74 Charger has "luxury ride" features incorporated into way the rear leaf spring mounts. That extra rubber and the age of the springs is likely letting the axel move around a little too much.

As a kid, had a 53 Olds with a warmed over J2 bored to 394 and a 50 Olds stick transmission, basically same as Cad Lasalle.

Continually breaking rear joint. One day while replacing likely my 5th one, had rear wheels off the ground and drive shaft out. Happened to spin one of the wheels while watching pinion yoke. It rotated in a very irregular circle. Turns out that it was tweaked, likely the first time I broke a U joint. Replaced it, never broke a joint again.

I did note however that you have replaced yoke already. Always believed that joints with zerks were much weaker than those without. Could be urban legend, but never have run any with
Zerks. Always believed that Spicers are the best.