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Thank you Fratzog.
I knew those joints were not right! I even brought the driveshaft to the parts store and showed then.. I asked? Should these things stick out like this.
I said I assembled this thing with my bare hands.
Cups slid right into place. No pressing, Pushed the inner c clip on with my thumb and it was done!
I will raise HELL today at the parts store for the right u-joint.
Just to think? Ive been driving on these joints for two years.
Thanks again everybody!
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They might work fine, but counter guys are just that, most don't work on cars so be careful with their advice.
President, New England chapter of Coronetaholics anonomous.
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As theman440 said, go in and ask for a 7260 U-joint. If they give you the deer in the headlights look, tell em it doesn't require a fart can to sound cool. Then ask em to cross reference one of these part numbers..
Moog part number 245 (non greasable) 246 (greasable) 315G (premium greasable)
I love Mopars so much I'm date coding the skid marks in my underwear.
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I went over to my Parts place. Told them we need to review the proper u-joint for my 67.
The computer showed #246 as the u-joint.
They looked up my purchase info based on my phone number as they always ask for!
Yup! #246 bought in Aug 2012.
But? He says there is also another option. The #315G. Its a smaller u-joint.... He said...
Hello Mcfly... The ones I have are too big from cross to cross by a half inch total.
I bought the #315G
IM HAPPY!
Thanks again for the second eyes of wisdom...
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Nope! The 315G is the same as the 246 in size....
I referenced the spicer 7260 Joint and come up with The precision joint number #347
I will request to see that joint when I had back their 315Gs they sold me.
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Update:
I have been running the 315G joints for a few weeks ( drove it twice )
The 315s fit tighter than the 246 joint, yet still patrude out of the yoke.
Anyway: The vibration at highway speed is really bad! That dreaded whaaa whaaa beat frequency at 62 miles per hour.
I brought home all my vibration analysis equipment and collected vibration data.
Bump tested the drive shaft while installed in the car. I did 5 tests. The shaft ring down frequency came in at 4495 CPM.
I connected my balancing equipment and monitored phase and amplitude. At about 2250 rpm the phase became unstable and amplitude jumped to 1.4 mils displacement.
At about half of the ring down frequency my vibration issues appear.
My joint angles are correct, thus no 2x alignment frequencies. Also no 2x vibration was seen in the FFT spectra.
loosenss is the only unknown. I do have a worn tail shaft bushing and the tranny mount is original.
Thoughts?
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Did you get the drive shaft balanced with the slip yoke on? That's the first step. Not too worried about the trans mount unless you can really push the tail shaft up a lot. On the bushing, they all have some play, they are never perfectly tight. How far can you wiggle the shaft in the bushing?
President, New England chapter of Coronetaholics anonomous.
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I can wiggle the Trans yoke a ton! I tried to balance the shaft in the car while on jack stands. I never gained ground. It wanted weight at 150. Run it. Then it wants it at 300. Back and forth with ever increasing weight.. Unstable phase.. Perhaps I should have tried at a lower speed?
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I THINK I FOUND IT!
Its drive line angles!
I measured my pinion and transmission with a digital angle finder that measures 0-90 degrees.
The rear pinion was at 86.1 deg down slope.
I measured the tranny angle and it was at 88 degrees. I just assumed it was up slope.... I bought two 2.5 degree wedges for each axel pearch and ended up within .6 deg.
AWWWW.
EQUAL AND OPOSITE.
NOT EQUAL...
Re checked tranny. its also DOWN SLOPE. SO?
Im within a half degree with both angles down slope. There is the problem!
That explains why when I removed those 2.5 degree shims with new u-joints, the car became a buzz box at 62 mph
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If you can move the trans yoke (a bunch) it is possible the bushing has fallen out or very worn out - it will cause a nasty vibration, had it happen to me.
