four wheel drive ?s

[1968k10blue]

I have a rockwell t221 and was wondering what it would take for me to be able to tell the difference between gears better, it just has a fairly sloppy warn out shifter. the other question is, when I engage the locking hubs and drive down the highway, it will vibrate like crazy. I think it has to do with on the driveshafton the upper U-joint there is a block with a second U-joint that only allows movement in one direction, not both, is this normal equipment? I would get a picture but it would be very hard to get a decent picture with the tranny crossmember in the way. thanks for the help in advance guys

[Bigdav160]

Double cardan joint? Yes if it is worn out it will cause a vibration.

[obijuan]

Dont lock the hubs in on the highway. Fixed.

[1968k10blue]

on that joint, how do I figure out if it is warn out? it doesnt seem to move unnaturally, also I dont want to have to get out and re-lock the hubs every time i need the 4 wheel drive come wintertime

[yellowbomber]

First question: The 221 linkage is famous for being sloppy. wasn't the greatest when new so add 45 years. By far the easiest access is the to remove the trans hump in the cab. After that the whole works are very clear.
There are 3 bolts that hold a 2 part mounting bracket to the trans case. Make sure those are tight. the bottom driver's side likes to back out.
The stick mounts to the bracket with a nylon bushed shouldering bolt. Take that apart clean and lube.
There is a shoulder bolt with a 3/4" long shoulder that slides in a slot to actuate the selector bar. I have had to build that bolt up in the past by welding and grinding back to size if it is worn or grooved. The play between that bolt and the bar slot is often the worst part of this system and what translates into the worst sloppiness.
Below that the bar is attached to 2 clevises by smooth pins. These will sometimes get real sloppy too so remove clean, check for excessive play, lube and return.

Second: The double carden is almost always overlooked for lubing and will cause vibration when bad. It is a device that takes the place of a carrier bearing to allow steeper angles in a shorter amount of length. It is still used on new trucks today and works well and for a long time if lubed. It works by spring pressure to hold that joint in a centered position to keep it from vibrating. Sometimes you can clean it, lube it and be o.k. other times it needs to be replaced. R&R involves pressing out the adjoining u-joints and can get tricky. Most take it to a driveline shop or order the new front shaft.

[LONGHAIR]

It could also come from the axle joints. Un-like a driveshaft joint, they do not have to move whenever the truck does, so they can get "stiff" from dried-up grease and rust. Usually this stiffness happens in only one side of the cross, because the steering flexes the other side. But then when the hubs are locked in, the "stiff" side needs to flex too. The steering leverage is usually enough to overcome it as far as forcing it to steer, but it can cause a wobble or vibration.

[1968k10blue]

Thanks guys, I will have to take some time and check it out. You say that the cardon joint is spring loaded? I am able to easily move it by hand, could this be a problem?

[maxwoof]

On my 62, the shift bar attaches to the transfer case shift levers with 3/8" pins. I bought all new pins. Drilled the holes in the linkage bar out to 1/2" and then used 1/2" od by 3/8" id bronze bushings. This tightened things up considerably. I think I got all pieces from McMaster Carr.

[1968k10blue]

does anybody have any info on the cardan joint? and if since I can move it by hand does that mean I need a new one?

[LONGHAIR]

It sounds like it is in need of a rebuild. They have an internal spring and bearing that keeps both joints at equal angles to each other. This makes them feel fairly stiff in your hands.

[1968k10blue]

how would I go about doing that?

[yellowbomber]

Sorry 10Blue, the server said busy last night and wouldn't take a reply.

If you can move the carden joint up and down or side to side noticeably by hand, while mounted in the truck, then it is worn. Also the slip splines can get bad when not lubed, and cause a wobble. I have seen several slip splines get bad enough, that they broke trans tailshafts from being frozen when the suspension cycled.

Like I said in my above post, both carden u-joints need to be pressed out, (probably due anyway) to access the joint. often times the joint is not repairable, and a new one must be welded to the driveshaft, or like above, just order a new shaft.
Depends on how comfortable you feel taking it apart. If it is shot anyway, good learning experience.
I have never sourced the spring, ball or seals so I'm not sure if you can or not, maybe google spicer parts?

[1968k10blue]

I am starting to think that we arent talking about the same part, the description sounds right but by looking at it, it does not seem to need to have anything pressed out can you expand on that? it literally just seems to be a u joint attatched to a small block that only allows one direction of movement. whereas a u joint allows two directions of movement. to me it seems like basically an extension of the driveshaft, which again matches the description above, but to me seems like the point is mute to have only 1 direction of travel

[1968k10blue]

nevermind i lied I do see how it needs to be pressed out, I might just need to live with it for winter though, no time or money to do so