RoadRanger/Eaton Clutch check?

[Brian Diehl]

How can I check the current condition of my clutch on my Eaton Autoshift without having to remove the transmission from the motor?  I looked around yesterday and could find no way to ascertain the condition of the clutch.  Thanks in advance for any ideas ...

[lloyd]

Depending on the type of adjuster you can look at how many threads are still out of the clutch housing. Other than that I don't know of a way to check for wear without removing the clutch. How many miles were there on the truck you got the engine/trans from?

[Brian Diehl]

The truck had 612,000 miles on it...  I have no records to indicate when the last clutch was put in ...

[TomC]

If the clutch was not misused, 600K miles can be about 3/4 worn clutch on a autoshift.  I had a 13 spd transmission on my truck-when I stopped driving it had 1.2 million miles on the original clutch!  Typically if a properly adjusted clutch engages around the middle of the pedal travel, it is OK.  If it is near the top of the travel-maybe time to redo.  You didn't change the clutch before installing?  Good Luck, TomC

[Brian Diehl]

  You didn't change the clutch before installing?  Good Luck, TomC

Tom, The engine is not in yet ... I was trying to see if there was anyway to see the condition of the clutch so I could avoid pulling it apart if at all possible.

It doesn't sound like there is anyway to tell .. so I'll have to pull it apart unless I hear any other ideas.

[boogiethecat]

If your engine is out, just replace it and the throwout bearing n pilot bearing.  A new clutch right now is waaay cheap as compared to having to change it when/if it blows- being that your engine is already out, 99% of the work is already done. It's a very simple task at this point- a total no brainer and very few bolts to wrench...and just changing it now is the best insurance you can buy for peace of mind and knowing what's really in there...

[NJT 5573]

Brian, I take it the trans is still mounted to the engine. About all you could tell is by looking thru the inspection hole. You could look at the distance from the throwout bearing to the clutch brake to see what you have. If the clutch brake locks up with the clutch pushed in, it probably still works ok. While the clutch is pushed in you may be able to wiggle each disk back and forth (around) to get an idea of spline wear. I would talk to someone in a fleet to ask how they last. I don't think auto shift would save much clutch as most truckers only use a clutch to start out anyway. It probably has a big bad clutch that will last forever. If its in adjustment, I'm a big fan of "if it ain't broke don't fix it". If you went rebuilt you could get less clutch than you have now, not all rebuilts are equal, Lipe Rebuilt is the only one I'd use, otherwise new + pull and surface flywheel. The only way I know to destroy these clutches is to pull the center out of one of the discs. Even then I won't usually change the whole clutch, I'll just replace the discs. If the discs are properly aligned with the spacer and each other I think the clutch is good. These clutches are designed to pull over 100,000 lbs 24/7. If this clutch checks out at all it should last forever in bus use. It will not just fail and let you down. When they do fail and pull the center out of a disc they will still lock the other disc and bring you home, especially with only 40,000 lb. Big horsepower probably means a new input shaft with the clutch job. The shaft wear is where the disc splines ride on the shaft. Grease the bell fittings and throwout bearing and run it. If it fails right away your dealer can give you a replacement, if you take it apart, you can buy a replacement. This isn't a 15 inch single disc bus clutch so its overkill.

[Sam 4106]

Hi Brian,
I have no personal experience with Eaton Autoshift, only what I have read, and I read a lot. However, based on my reading I believe that the only time the clutch is used is to start, and presumably to stop, the vehicle. If that is the case, your clutch with only 612,000 miles should be in good shape yet. I understand your desire to know for sure before you install the unit into your bus but I believe you would be way ahead by just installing the unit as is. I believe you will have enough work doing the swap without worring about the clutch. Since you are the one that has to live with your decision please take this as just an OPINION.

On another topic, how are you adapting your 24v  bus electrical system to the 12v system of the truck engine?
Best wishes on your project, Sam 4106

[Brian Diehl]

Thanks for the feedback guys.

One idea provided to me by IM was to buy some long bolts to support the tranny to bell housing joint.  Then slide the two apart on the bolts.  Then, I might be able to actually see the current thickness of the clutch plates.  It sounds like a good idea, but I wonder if the pressure plate has any "view ports" in it that will allow me to see the clutch plates...  Still contemplating what to do ...

Sam, I'm using a 50amp Vanner Equalizer to provide all the 12 volt power the engine and transmission computers need.  They will stay 12 volts.  I'm replacing the 12v starter with a 24v starter and have the 12v alternator removed ready to put the 24v one on.  I picked up a 270am 24v 50DN belt drive alternator from Nimco for $500.  Now I'm just waiting for it to arrive.

Last night I started the next phase of the project -- removing the engine/tranny from the bus.  I made good progress last night and have half of today off (comp time).  I'm hoping that by the end of the weekend the back of the bus is no longer supporting a powertrain ...

[lloyd]

If you are going to pull the trans back that far you might aswell remove it and drop the clutch and inspect it. What ever you do don't let the trans hang on the engine partially out of the clutch, this will damage the plates and then you will have problems.

[NJT 5573]

Brian, the surface area of the disc seldom fails. You most likely have a button clutch anyway, (all metal). In most cases, its the center of the disk that fails and not the friction surfaces. I have not seen a truck bell that did not have an inspection/adjustment cover on the bottom.

[Brian Diehl]

So, what am I looking for when I look in the area behind the clutch in the exiting inspection area?  Anyone have any pictures that will educate me on what I'm looking at in that area.  FYI, the area is where the (I assume) throwout bearing grease zerk fitting is at.