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Topic: Houston, we have a problem! (Read 709 times) previous topic - next topic

Houston, we have a problem!

In prep for a camping trip this weekend, I took the coach out for a short spin this evening to get some fuel and see if everything is working well.  Unless it's my imagination, the steering is much more responsive with less play after being lubed.  That's the good news.

You might recall that when I lubed the chassis last week I was concerned about how much grease the drive shaft spline was taking.  I stopped, read some posts about it, then continued greasing the spline.  I was supposed to see grease come out of some hole in the end of shaft but never did.  What I saw was grease coming out around the edges of an approx. 3" diameter blue rubber or plastic plug.  Well, today when I pulled back into the parking lot, that rubber plug fell out along with about 1/2 - 2/3 cup of grease.  I of course didn't know it at the time but saw the plug when I was in my car leaving to come home.  Two pictures of the plug below.

A few questions:  First where is the relief hole that the grease was supposed to come from?  Could it have been plugged and I over-greased the spline and forced this rubber thing out?  Second, can I just put it back in?  Finally if I do put it back in, is it safe for us to go camping tomorrow?

EDIT: When I looked at these photos blown up after I did this post, I saw a dark dot in the center of the plug.  Went to the garage and forced a screwdriver through the hole.  It was totally crusted up with what I imagine was old grease.  I guess questions 1 and 2 are now answered.

Thanks in advance,
Mark
Mark Duckworth
2003 U320 4220
Build 6199, Motorcade 17971

Re: Houston, we have a problem!

Reply #1 –
I would say it would be safe to use the coach. You can probably put the blue plug back in. I knew a guy that I worked with that used a whole tube of grease every time he greased a motorhome. I don't know how he found places that would hold that much grease.
previous 1984 35 ft ORED 250 HP 3208 Cat       
previous 1998 40 ft U295 CAI 325 hp Cummins
previous 2003 40 Ft u320 build #6140 450 Cummins M11.                                                         
1999 Mazda Miata
Ron, Nancy, Tipper the cat, Max The dog
1997 U 270 36 ft build number 5174 8.3 Cummins

Re: Houston, we have a problem!

Reply #2 –
Quote from: Mark Duckworth –
A few questions:  First where is the relief hole that the grease was supposed to come from?  Could it have been plugged and I over-greased the spline and forced this rubber thing out?  Second, can I just put it back in?  Finally if I do put it back in is it safe for us to go camping tomorrow?

Mark,
For #3 you should be fine if you just put the plug back in as it most likely has slung most of the excess grease out.    You just hydraulically pushed the plug out when the spline moved inward.  The big thing that you need to check is if on your coach, is the fast acting brake valve located just above the spline.  If it is there look to make sure that the exhaust ports aren't clogged with grease.

Pamela & Mike
Pamela & Mike 97 U 320

"It's not what happens to you, but how you react to it that matters."

Re: Houston, we have a problem!

Reply #3 –
That is just the plug  in the end of the slip yoke. Put it back in and you'll be good to go.
91 GV U300 Unihome 40' Build 3811
6V92TA Detroit

Re: Houston, we have a problem!

Reply #4 –
Repair completed!!

Quote from: Pamela & Mike –
Mark,
The big thing that you need to check is if on your coach, is the fast acting brake valve located just above the spline.  If it is there look to make sure that the exhaust ports aren't clogged with grease.

Pamela & Mike
Valve looked OK.  Less grease slung around than I imagined.  Cleaned it up.

Quote from: stump –
That is just the plug  in the end of the slip yoke. Put it back in and you'll be good to go.
It's back in.  Matter of finding the correct lever applied at the right points.

Thanks everybody for your help!

What causes the spline to move back and forth?
Mark Duckworth
2003 U320 4220
Build 6199, Motorcade 17971

Re: Houston, we have a problem!

Reply #5 –
Quote from: Mark Duckworth –
What causes the spline to move back and forth?

Mark,

Here is an over simplification as to the movement. As the coach moves up and down while you travel (think ride height, air bags, & torque tubes) the axle is moving with the road conditions. The difference in this movement is made up in the axle spline.

Pamela & Mike
Pamela & Mike 97 U 320

"It's not what happens to you, but how you react to it that matters."

Re: Houston, we have a problem!

Reply #6 –
Quote from: Pamela & Mike –
Mark,

Here is an over simplification as to the movement. As the coach moves up and down while you travel (think ride height, air bags, & torque tubes) the axle is moving with the road conditions. The difference in this movement is made up in the axle spline.

Pamela & Mike

Ah, that make senses.  I was thinking strictly forwards and backwards and not taking into consideration the other dynamics.  Thanks, Mike.
Mark Duckworth
2003 U320 4220
Build 6199, Motorcade 17971

Re: Houston, we have a problem!

Reply #7 –
Quote from: Mark Duckworth –


What causes the spline to move back and forth?

One end of the drive shaft is connected to the transmission which is bolted to the chassis rail.  The other end to the rear axle.  As the rear axle goes up and down over bumps the splines go in and out to accommodate the change in "distance" between the two.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Houston, we have a problem!

Reply #8 –
Quote from: wolfe10 –
One end of the drive shaft is connected to the transmission which is bolted to the chassis rail.  The other end to the rear axle.  As the rear axle goes up and down over bumps the splines go in and out to accommodate the change in "distance" between the two.

Thanks, Brett!
Mark Duckworth
2003 U320 4220
Build 6199, Motorcade 17971

Re: Houston, we have a problem!

Reply #9 –
If and when you use your blocks on the coach,look at the drive shaft,you'll see how it moved.Put mine on the blocks and the
driveshaft got a couple of inches longer.
96 U270 BUILD 4810
85 380SL
Drummonds TN.
 

Re: Houston, we have a problem!

Reply #10 –
Reply # 6 will give you a picture of what happens.
Ride height question
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
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2014 Grand Cherokee Overland
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