1 Piece driveshaft

[65chevysub]

Is anyone running a 1 piece driveshaft in their burb? I had one made back in the 90's, but it seemed to vibrate more than the 2 piece, even with new U-joints. I have some literature from GM on the '65 Chevy trucks, and it says that the 'burbs all had 2 piece shafts but the pickups only had a 1 piece. Is there a reason for this. I'm wondering if I should take my 1 piece to an actual driveline specialist and have it checked, as it has regular washers as weights on it, and it was done by a muffler/ driveline shop.

[hd74]

i piece driveshaft on my 1963 gmc

[Corts60]

My '60 GMC suburban and my old '60 GMC truck both had factory one piece driveshafts. I think maybe the two piece shafts might have come out when they changed the frame in '63.

[Captainfab]

My '66 Brub has a one piece driveshaft. I assumed all Burbs and shortbed trucks had one piece driveshafts, and all longbeds had the 2 piece. I've not seen a shortbed or Burb with a 2 piece driveshaft.

[RockTonka]

66 burb here with two piece drive shaft...

[padresag]

perhaps it is the ones with the 4 speed that have the 2 piece and the 3 speed and a/t with the single d/shaft???
ron

[tincan1966]

I learned from a previous project that driveline vibrations can be associated with the angle of the trans and pinion. Regardless of either 1 piece or 2 piece, the trans and pinion angle have to be the same.
I learned this after finding out the previous owner of my '69 C30 had shimmed up the trans mount about 1/4".
I found a good website that explained it all, I wil try to find it again and post the link

[VictoriaHardware]

My '66 Sub is all original and has a one piece. It has a 292/Powerglide

[65chevysub]

Thanks everyone. Mine is the 2 piece, factory. It originally had the 292, with a P/G trans. The biggest problem I had was my carrier bearing kept breaking where the spot welds were on the threaded plate. I finally drilled them out and put 4 small bolts, lock washers and nuts on it to keep it together. So far so good, on the fix.

[hemifalcon]

My '65 has a one-piece shaft.. It's a 4speed with 292... I prefer the heavy 1-piece unit rather than the multi-piece shaft with the center support bearing. Trucks that are 4x4 would obviously benefit from the extra articulation point.

[padresag]

Originally Posted by hemifalcon

My '65 has a one-piece shaft.. It's a 4speed with 292... I prefer the heavy 1-piece unit rather than the multi-piece shaft with the center support bearing. Trucks that are 4x4 would obviously benefit from the extra articulation point.

that blows my question out of the water
it does not seem to be make specific either(chev or gmc with different rear suspensions). there must be an explanation for it some where
in a 4 x 4 the independent t/case acts as the centre supprt except for the frt shaft
ron

[Brad54]

My '62 Suburban (I've cosmetically changed it over to '61) was factory V8, Granny 4spd, 1pc driveshaft, with the slip-yoke built in to the driveshaft.

I converted to a 4spd OD manual trans, and had a new 1pc driveshaft built by a driveshaft shop.

My vibrations have more to do with worn shocks, worn rear suspension bushings and worn front suspension. I also lowered the truck a bit, and never got around the resetting the rear pinion angle, though it's probably only out by a degree or so.

-Brad

[64fleetside]

One piece on mine, was ?/4 speed now 350/700r4.

[MusicMan70]

My 61 GMC 305 V-6 and SM420 , had the two peice driveshaft. Since the OD conversion, I have a one peice DS.

[RockTonka]

Mine from above was 283/PG with 2-piece...??? Anybody see a pattern??

[rustyrodknocker]

My burb was converted to one piece with th350 doin the same to my panel.
Posted via Mobile Device

[Captainfab]

My '66 Burb was originally a 283/PG with a one piece.

This is all interesting info., I just don't see a pattern to the one piece/two piece driveshaft situation. I wonder if it had to do with where the truck/burb was built? Mine was built in the Fremont plant.

[MikeS.]

My 63 4x4 is one piece. My 66 LB truck was 2 piece.
Posted via Mobile Device

[Keith Seymore]

Driveshaft critical speed is what determines the allowable shaft length.

Critical speed (the point at which the shaft bends and starts swinging like a jump rope) is a function of shaft length, diameter, material and rpm (which is a function of vehicle top speed and rear axle ratio). Plus - if there is some odd system resonance that the shaft is responding too that can cause problems.

This is why trucks that are somewhat similar might have a difference between one piece and two piece. Could be the same truck but with a different rear axle ratio, for example, that drives the different release.

K

[MusicMan70]

Originally my 1961 GMC suburban (V-6) 2wd had a 3.92 rear ratio with Trac Loc and a two peice DS

[Captainfab]

My Suburban originally had 3.73 gears.


Mr. Seymore, I would like to hear your input regarding the standard top mount carrier bearing (as seen in post #5 above) versus the heavier duty carrier bearing that mounts on the bottom of the trailing arm crossmember, as more commonly seen in C20 and up trucks.

I'm not a fan of using the light duty top mount carrier bearing with small diameter shafts in a higher horsepower/performance based truck. I have always used the HD carrier bearing and larger diameter shafts with virtually no issues. There is a thread in the 'Racing and High Performance' section, discussing the durability of the LD carrier bearing and shafts in a racing application.

[Keith Seymore]

Originally Posted by Captainfab

My Suburban originally had 3.73 gears.


Mr. Seymore, I would like to hear your input regarding the standard top mount carrier bearing (as seen in post #5 above) versus the heavier duty carrier bearing that mounts on the bottom of the trailing arm crossmember, as more commonly seen in C20 and up trucks.

I'm not a fan of using the light duty top mount carrier bearing with small diameter shafts in a higher horsepower/performance based truck. I have always used the HD carrier bearing and larger diameter shafts with virtually no issues. There is a thread in the 'Racing and High Performance' section, discussing the durability of the LD carrier bearing and shafts in a racing application.

To be honest, I don't have a lot of experience with 2 pc shafts in race/hi performance applications.

I have always converted to a one piece (when I could get away with it) for simplicity's sake.

Intuitively, though - bigger is going to be better when talking about center bearings and shafts, in this case....

K

[Captainfab]

Thank you for your reply

Regarding the carrier bearings. For me it is a no brainer which one to use, when you compare the two.

Originally Posted by Keith Seymore

To be honest, I don't have a lot of experience with 2 pc shafts in race/hi performance applications.

I have always converted to a one piece (when I could get away with it) for simplicity's sake.

Intuitively, though - bigger is going to be better when talking about center bearings and shafts, in this case....

K