Hey guys ... So I have a 292 unlock and t98 4 speed with granny gear. It is in a 56 f250 long bed.. im trying to figure out a driveshaft for it.. the trans doesn't have a slip yoke it's got a flange yoke. Do I have to use a 2 piece drive shaft or can I use a 1 peice.. I don't plan on hanging on to the trans for very long just want to get it running so the wife will be happy. Maybe I could find something at the junk yard ? Thanks Dan Sent from my SM-G950U using Tapatalk
The most correct answer is that you need a slip yoke in the driveshaft. If the rear axle were solid mounted to the chassis, the slip yoke would not be needed as the driveshaft wouldn’t change length with suspension movement. If your springs are really heavy duty, and you carry no loads in the bed, and run a lower air pressure in the rear tires, you might get away with no slip yoke in the short run. But, even at that, there is likely to be a small amount of driveshaft push/pull which will stress the engine/trans mounts and springs, spring bushings, etc. Your call. Ray
Ok cool do I can put a slip yoke in the trans and then be all good with a one peice.. thanks and it's a 10 spline correct.. what care or truck should I look at to get the slip yoke Sent from my SM-G950U using Tapatalk
Go to the junk yard and get a two piece drive shaft, it will have a slip joint, from a later model Ford pick up. Ford used about ten different configurations of drive shafts in those years. I bet one of them will work. I found one that was a bolt in for the front drive shaft of my o/t four wheel drive. Replaced that wimpy stock shaft. I had to do some u-joint widzardy, but got it done! Bones
I generally have problems looking for odd duck parts since wrecking yards don't let you in anymore. When you do find the part online, it is wrong when it shows up. It also is going to cost you money to get a driveshaft made for what you admit will be a temporary fix, so why not make peace with your wife and look for what you really want in the long run?
There isn't a slip yoke to go into the back of the transmission.You need a drive line with a slip yoke on it.A male stub and a female slip....
Originally, it probably had a 2 piece driveshaft with a mid bearing, with a slip yoke at the bearing. There is a property of driveshafts called critical speed. At certain rpm, it will start to whip like a jump rope. This is dependent on a number of factors like length, stiffness, and weight. This will cause significant vibration even with a perfectly balanced shaft. 2 short driveshafts can handle higher rpm than a single long driveshaft, and are still used on long wheelbase trucks today. Some modern vehicles have longer one piece shafts by using a large diameter, aluminum(or composite) tube that is stiffer and lighter than typical steel tube.
I have a sm465 in my AA flatbed, it has a fixed yoke on the output shaft. I scrounged junkyard shafts with a carrier bearing set up . The slip is on the rear shaft. As bones said, you could find a later model two piece shaft from a pick up. The diameter of the shaft will be bigger than a car shaft to prevent the harmonic vibrations that relic stew brings up, and eliminate the need for a carrier bearing set up.
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