Ball and trunnion to u-joint conversion?

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Aaron65

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Well, 4 years after having my ball and trunnion boot replaced, it let go in spectacular fashion on the freeway; it sounded like a blown tire was hitting the bottom of the car.

So, I guess the reproduction boots aren't much good, so I'm probably going to convert to a u-joint. I think I've seen this somewhere before, but has anyone done it? I'll probably have the local driveshaft shop do it, but I'd like to go in with as much information as I can. Thanks!

Aaron
 
"A good" shaft shop can do this. Many 4x4's use a slip yoke / spline setup on the shaft.
 
Earlycuda.org has a parts list to build a new shaft. Converting ball and trunnion to u-joint.
 
I did it... After my boot exploded like you described...

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What makes the boot explode? Sounds like pressure builds up inside? Should it be air-tight? I didn't think so.

Jeep Wagoner guys pioneered the sliding yoke retrofit, since some used the same ball & trunion U-joint PN. I have seen some new sliding yoke driveshafts for sale on ebay, but didn't investigate. They look like perhaps a front axle for a FWD, so might not be long enough. They are affordable though (<$200, I recall). BTW, if faced with a different sized rear U-joint, there are adapter U-joints for various paired sizes.

Personally, I have enough B&T rebuild kits (no, not selling) to last my 2 early A's for life.
 
Mine never let go, but the trans did! It was cheaper to get a 67 trans with a splined output than rebuilding my 65, then I had to get a driveshaft, then a shifter, then.....lost track.
 
Well, 4 years after having my ball and trunnion boot replaced, it let go in spectacular fashion on the freeway; it sounded like a blown tire was hitting the bottom of the car.

So, I guess the reproduction boots aren't much good, so I'm probably going to convert to a u-joint. I think I've seen this somewhere before, but has anyone done it? I'll probably have the local driveshaft shop do it, but I'd like to go in with as much information as I can. Thanks!

Aaron
I have one for sale. PM me if interested.
 
They don't really explode; they just tear, and whipping around at driveshaft speed finishes the job. It sounds like a card in the spokes of your bicycle wheel times 10.

65ChargerDart, I'm probably going to go the new driveshaft route, but I'll keep you in mind. Thank you.

I haven't done anything about this problem yet. The Dart's in storage for most of the summer; it's kind of my colder weather old car. I have a spare driveshaft in the garage that I'm going to take over to the shop sometime this summer, and when I bring the car home to do some work on it, I'll swap it out then.
 
What are the dimensions of these driveshaft conversions? I have a nearly new one (made by Denny's driveshafts) that was made for a Dart that had a truck transmission in it that is very similar to the one pictured.
3 1/4" universals, I believe the shaft and slip yoke goes from 60" to about 66" max. I would sell it cheap.
 
Trunnion?????? Yes WHY those trunnion style 4 speeds bring SOoooooo little $$$$$. Hint: to those trying to sell them for big $$$$$$ here and there.
And try to find a complete trunnion rebuild kit or get that rusted pin out of the old unit!!! LOL
 
My driveshaft is in the 56" range when mounted in the car; since it's a wagon, it's on the Valiant wheelbase, so it's shorter. Too bad!
 
They don't really explode; they just tear, and whipping around at driveshaft speed finishes the job. It sounds like a card in the spokes of your bicycle wheel times 10.

65ChargerDart, I'm probably going to go the new driveshaft route, but I'll keep you in mind. Thank you.

I haven't done anything about this problem yet. The Dart's in storage for most of the summer; it's kind of my colder weather old car. I have a spare driveshaft in the garage that I'm going to take over to the shop sometime this summer, and when I bring the car home to do some work on it, I'll swap it out then.

You would have to have a new driveshaft made up with my conversion anyway. I had the conversion done and new driveshaft made up for the 8.75 diff I installed.
 
Why not just buy one without? My 65 has one on it now but I’ve got a 66 valiant without the b&t ready to go in. Seems it would cost less and be original. Just my opinion
 
The '66 driveshaft won't match up with the flange on the back of the '65 transmission.
 
Trans and driveshaft will work. I bought a driveshaft from someone that had the trans swapped and driveshaft to match.
Im installing a newer 904 and a slip yoke driveshaft.
 
The '66 driveshaft won't match up with the flange on the back of the '65 transmission.

Hmmm. I wasn’t aware of that. I’ll have to double check. I have a 3 SPD column shift and both look identical except the ball and trunion. I’ll slap it in the car and see. Have to switch out k frame and engine and trans has to come out. Was under the impression that they could swap out
 
Hmmm. I wasn’t aware of that. I’ll have to double check. I have a 3 SPD column shift and both look identical except the ball and trunion. I’ll slap it in the car and see. Have to switch out k frame and engine and trans has to come out. Was under the impression that they could swap out
Put a 66 trans and driveshaft in a 65 and earlier without trouble. Not sure why you are switching the K but /6 and V8 take the same K member.
 
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