Plastic Sheath On Slip Yoke Falls Apart/is Pushed Out

[Noid93]

It has been a contiuously been a problem on my truck with the plastic on the slip yoke splines breaking and pushing out. How important is it, what is its purpose, and how bad is it to run it without??? Thanks for your help and info...

CURT

Noid93

[Bollweevil]

The main purpose of this coating is to cushion, and reduce the shock load on the slip yoke. A slip yoke is just what the name implies. As the suspension goes though its normal travel, the yoke moves in and out. Without the coating the splines tend to fret,or brinell. and wear a lot faster. These joints don't always get all the lubrication that they need. Another aspect of these coatings is that they don"t require as much lube. or as much clearance. In other woods you can have a tighter joint with a much lower wear factor. Now. with the coating gone, you have increased clearance in the splines, which will only get worse until it fails. Like a drive line that is out of phase, or out of time it will shake and vibrate. The best time to fix it is now, instead of on the side of the road. James

[Noid93]

The main purpose of this coating is to cushion, and reduce the shock load on the slip yoke. A slip yoke is just what the name implies. As the suspension goes though its normal travel, the yoke moves in and out. Without the coating the splines tend to fret,or brinell. and wear a lot faster. These joints don't always get all the lubrication that they need. Another aspect of these coatings is that they don"t require as much lube. or as much clearance. In other woods you can have a tighter joint with a much lower wear factor. Now. with the coating gone, you have increased clearance in the splines, which will only get worse until it fails. Like a drive line that is out of phase, or out of time it will shake and vibrate. The best time to fix it is now, instead of on the side of the road. James

I understand completely what the purpose of the slip yoke is, and had a good idea what the platic was for, but what is the best way to fix this??? Can a driveline specialist re-plastic it, or do i need to replace the whole drive shaft or /weld a new male splined end on the shaft/and or a new slip yoke??? Thanks for the help.

CURT

[Bollweevil]

A good drive line shop can replace the male end for you, they will need both sections in order align front and rear yokes, when welding the new splined end. You could let them check the female end for excessive wear as well. I would ask some one at a local trucking company who they use, for this kind of repair. Another option would be to find a good used assembly. You have to be careful if you do this though. You could spend as much, or more than it would cost to repair yours. I have never heard of anyone re-coating one. James

[Noid93]

A good drive line shop can replace the male end for you, they will need both sections in order align front and rear yokes, when welding the new splined end. You could let them check the female end for excessive wear as well. I would ask some one at a local trucking company who they use, for this kind of repair. Another option would be to find a good used assembly. You have to be careful if you do this though. You could spend as much, or more than it would cost to repair yours. I have never heard of anyone re-coating one. James

We have a CATCO localy that takes care of most of the driveline work on anything from a pickup to off road equipment. I will inquire with them.

Thanks again, PS any help on my transmission post???

[Noid93]

We have a CATCO localy that takes care of most of the driveline work on anything from a pickup to off road equipment. I will inquire with them.

Thanks again, PS any help on my transmission post???

GREAT NEWS, Just got my drive shaft fixed.... CHEAP. Found a new takeoff intermediat shaft at a boneyard for $100. 2 cuts, one weld, one balance.......

$85!!!!!! Pretty good price for the repairs especialy on a saturday. JR Advanced Driveline out of Chippewa Falls, WI.... 715-726-1181 Will ship most any where..

[Bollweevil]

Just the "peace of mind". is worth $185.00. That sounds very reasonable to me. Did you ever find anything about your transmission? I have never seen the inside of a Mack 9 speed. If it was an Eaton-Fuller, I would say that the retaining ring groove had broken out of the main shaft reverse gear, allowing the shifter clutch to pull reverse gear forward, on the shaft. That will leave you still in reverse when you select first gear, thus locking the transmission. When you put it back in reverse it slides the gear back on the shaft. Sometimes it will stay in place, until you need reverse again. If you can catch Herb's attention, I bet he could tell you for sure what's wrong with yours. James

[Noid93]

As goes the tranny battle, I have not found a quick fix for the reverse problem. PS. Its a 13 spd. I get buy as is, but i was just wondering if this has happend to any one else. I think its pretty clear to a tranny expert like yourself what would be wrong, but no ones got a quick remedy. I will probally run it until it becomes unoperable. If i need a clutch in the slow winter season i may tear it down, but it aslo has a few noisy gears(not major but still there) so i may not be to far off from a reman exchange deal. The noisiest gears are tenth(4 and 8 hole on the under drive) and eleventh (same hole just with the H/L box in direct. Its louder in one than the other. It just makes me wonder if i have just the right/wrong combo of speed and bearings making just the right resignation making it that way. I apreicate all the help from you guys. THANKS ALOT

CURT