3126 Owners

[P51bombay]

Question for you 3126 owners. I was talking with the mechanic the other day and he seems to think there is a trans bearing failing due to some noise that occurs at idle and on shut down.

When idling there is a sort of rattling noise that will go away when you either raise the rpm slightly or depress the clutch. It also is noticeable when you shut down and the engine causes the truck to shake as it comes to a stop there is a similar rattling noise.

This is in the T300 with a 10spd, the M2 I used to drive with a 6 spd made the exact same noise under the same conditions - I drove that truck for two years and it always did it, never got better or worse. Just looking for opinions - tech is good but more familiar with big engines so I'm wondering if this is something peculiar to baby Cat engines.

 

[greg334]

I have the same exact noise at the same speed but it is not a trans input shaft bearing, it is my clutch throwout bearing.

I was told if I were to not just replace the bearing but also re-bush the clutch shaft (or re-bush and replace the shaft if both are bad) and also use quality parts for a re-clutch, I would not have the noise 200k later.

Oh and I have a Cummins ISC.

 

[P51bombay]

I assume you mean the input shaft bearing right?

Eaton tranny?

 

[piper1]

Greg is right on, throwout bearing.

The shake is more likely the the ole CAT coming to a halt as it keeps having compression strokes with no fuel to continue the fun.

 

[P51bombay]

Well that is much better news than needing a reman tranny, anyone know what a clutch with TO and pilot bearing costs to R&R? Its an eaton 10spd OD. CTech says the clutch has about 30% left.

 

[piper1]

about 8 hours labor, Clutch cost depends on the clutch and new or re-man (a Spice/Eaton reman is a good clutch). Clutch comes with new throwout bearing and pilot bearings are cheap.

If you are keeping the truck for a while I would get the flywheel resurfaced (turned true) to enhance the life of the new clutch. Adds about 150 bucks to the job.

 

[greg334]

Piper,
You know I am getting too old, the clutch fork shaft should be looked at too, that was what I think I was trying to get at with the re-bushing thing. I don't even know if these lube engineers at these places hit them with grease.

The pilot bearing and even the flywheel surfacing is a given for any of my clutch work.

 

[davekc]

Throw out bearing is correct.
Replace the clutch in the process. Paid 380 on replacement for a Eaton at private shop at 60 per hour labor.

 

[piper1]

You ain't to old greg, I've never seen you post things like "well on my Brockway" or "you must have one of those turbocharger thingies, energy from exhaust..Bull****!".

You would be amazed at the shops that sell a clutch job without the flywheel re surface.

And your bang on about the crossshaft bushings, a good guy would check those too at a clutch replace.

Why I remember doing a clutch on a Dodge 900 once that...............

 

[davekc]

How about the Autocars and Diamond Rios

 

[bluejaybee]

I have owned several 3126's that all made the strange noise when idling. I never knew what it was, but only heard while on the outside of the truck. I have had throwout bearings making nosies before, that when you pushed the clutch it, they stopped and you could tell it on the inside. But, the noise I hear can;t be heard inside.