Hey any TECH on a single drive shaft in a 63 Impala. I want to go that way and need some advice. Thanks.....
I have no experiance with '63 Impalas but offer some thoughts: Isn't the frame an X shape? I think that makes it really difficult to use a one piece shaft. I believe the center driveshaft bearing is mounted in the middle of the X. If you did convert to a one piece shaft you would have to build a new floor tunnel as the shaft would rise higher in the tunnel. I would think you would have to cut the center of the X frame.
18 years ago I made the mistake of building a one piece shaft for that gen of Impala. Part of the reason for the 2 piece 2" diameter shafts is for clearance in the tunnel and for suspension movement. If you replace the rear of that stock 2 pc setup with a 2 3/4" diameter shaft, the larger OD shaft WILL interfere inside that X frame during normal street driving in a stock height car. Installing a single piece shaft inside that X frame is a bitch because of clearance. It's almost like trying to carry a mattress up a spiral staircase or fitting a BBC in a CJ-5 Jeep. In my eye, you would need to completely redo the stock frame to make a single piece shaft work properly and remove the hollow X. I have had my hands on ONE factory aluminum 409 car carrier bearing assembly. It is massively stronger than the normal lollipop piece of junk.
Yep, you are looking at a frame off, lots of modding to the frame and some mods to the floor. Alternatively, you can put a slip joint in the rear half, get a 409 carrier (as mentioned above) or get one of the Aluminum carriers from Inland Empire on Ebay. I was throwing carriers right and left. Then I got a new crappy one, rewelded it, and filled it full of urethane. I also rebuilt the back half shaft with a slip joint. Haven't thrown one since and I've been much rougher on it.
yea X frame cars have 2 piece drive shafts for a reason. It certainly wasn't to make them easier to assemble at the factory.
Another key suggestion is to make a new rear section with a sliding splined section, like a 4x4 front driveshaft has. The stock setup has the carrier bearing flexing due to suspension movement. If you use the sliding rear section, it takes the movement out of the carrier bearing and they last signficantly longer. It is not the bearing that goes bad, but the rubber holding it breaks loose.
unless you go to a full perimeter frame your stuck with the 2-piece driveline ans that is the weak link in pre 65' impala's. when i had my 60' impala with 348 i collected drivelines for spares.
I bought a 60 BelAir new. I still have it. The secret to making the center suport work is to tighten the bolts with the car at ride heigth. They last at least ten years then. My car should be hard on driveshafts as It mostly ran with 4.56's and 3.70's with an overdrive. The car has 300k+ on it. I would forget the one piece driveshaft unless you are prepared to build a new frame and floor.
The slipjoint on the driveshaft thing would be quite similar to what is on the 60/72 Chev pickup two piece drive shafts and would probably really help, especially with a car that was extremely lowered or bagged or did have a lot of extra power. Andy's suggestion for having it set at ride height before finishing tightening the support bolts is good too and one that I never thought of when I was working on them all the time.
I have no knowledge as to the original setup of this car. After reading alot of the replies I thought back to Jay Leno's 1966 RWD Oldsmobile Toronado and I thought why would he had chaged from FWD to RWD, I guess cause he can afford it.
Yes, good reminder to tighten the mounting bolts at normal ride height. So the carrier bearing is not pre-tensioned. You can help the carrier bearing by injecting silicone or polyurethane sealnt into the rubber bearing. The root cause of the problem is the bearing must flex in and out to allow for suspension movement. That is why the rear sliding shaft is the best solution. Put one in my 59 El Camino. Also dealt with the carrier bearing issues on my 60 El Camino. The cheap carrier bearings will separate at the base, just spot welded. Cure is to run an extra weld bead around the circumference so it does not break loose from the flat piece.
The Chevy 2 pc. drive lines are very small diameter. After twisting many of the originals in my '62, I found that a '60-65 Falcon drive shaft was just the right length. I cut a notch in the bottom of the frame, and opened up the center web a little. You could fabricate a reinforcement for the bottom of the X out of a large diameter heavy wall pipe, but I ran mine without it. You don't need to touch the floor, and the amount of the material you remove from the frame won't cause any problems. Never had another problem with the drive shaft, of course it now broke spider gears and axles. If you haven't already added a second upper rear control arm and reinforced the upper rear suspension cross member, do it know. It's a lot harder to do it AFTER you mangle it up.
I had a '59 Elco that was converted to a one piece driveshaft when I got it.. If I'm not mistaking the El Caminos were slightly shorter than the Impalas, I don't know if that makes a difference.
been running the slip yoke on the rear shaft since the early 90's on all my GMs (4 of them). After I put them in I rarely had a problem again with the center support going bad. I did the filling them with silicone and welding gussets, made them last a little longer....barely. The main thing is to re weld the bases on the cheap carriers and get the splined rear shaft. I've seen a 1 piece shaft put in but it had extensive frame mods to make it work.
Did a one piece conversion on a Rat motor 64 Biscayne, used a 9" extention housing length T-350 w/ brake, minimal triming on rear of tunnel if I recollect, it's been years. However it did work well, car was real fast. Of course a lot of beefing up of the rear control arms and the upper cross member..........
Andy is dead on the money with the carrier bearing adjustment. I learned this by the time I was 25 and working on customer's vehicles. One problem I see with Fishbeck's shaft pic is the rear slip yoke is inside the X and cannot be service without removal. Grease is cheaper than parts replacement. The rear shaft slip yoke should be at the pinion end, which is opposite of normal arrangement by shaft builders because we don't want to have a slip yoke like that to have possible water and dirt to be force fed into it. This is another exception to our standard rule like most Ford Broncos and a couple more. Most factory GM shafts like this have 2" x .095 wall tubing and all stock ones have a 1 1/8" spline and shaft thru the carrier bearing. Both are weaknesses if torqued on correctly with traction available. The stub shaft thru the carrier bearing is not made in the US any more, if it's made at all. The yoke that splines on to it isn't either that I know of. In my part of the woods, used stuff is very hard to find because original stuff was done at the end of '72 year trucks and my current shaft parts catalogs don't even show the parts had been available 15 years AGO. Damn, I rode i many of those vehicles when I was a pup.
Also, if your going to run it hard beef up the rear arms (the 409's had 2 arms). I've seen more then a few crossmembers cracked where the torque arm attaches.
I have seen the slip yoke on the other end. I didn't think about servicing it. Great, another thing to worry about.
I'll take a pic of my elco this weekend, I can't remember if I repair the rear crossmember on that one.
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