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Full Version: CM2250 Rear Structure Leak
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I have a 2012 kw W900B with a CM2250 ser# 79502726 620K miles. I pulled things apart to fix an oil leak at the rear structure gasket. I can see slight wear on the aluminum flywheel housing at the top right side exactly where it was leaking. Do this need to be machined or how critical is that?? Also since I have the pan off should I be shimming the oil pump regulator? If so how much?
That is usually a clear sign of truck abuse at some point in its life ...

If the engine is worked hard at high torque and lugged a lot .. or someone lets out on the clutch real hard a lot .. that is what causes that rear structure wear that you describe.

As far as fixing it.. would depend on how bad it was.. If its real bad, maybe you need a new one?.. or you could chance it, clean it up real good, and use some aerobic sealant in that area if your feeling risky and are prepared to pull it all back apart again if it does not seal.

(just the beer talkin' - being sarcastic )...
.. Might want to consider also to turn the torque down a bit, + always ensure to drive it in higher RPM's when power is needed (keeping it above 1500+ when a lot of throttle pedal is needed) .. and re-gear the rear ends to fit the application so that it does not have to put so much load/torture on the the engine .. or fire the driver if they are still abusing the truck ..lol

seriously though.. they don't fail like that on their own. Should also likely change the engine mounts out while your at it too.
Yeah I hear you on the torque/abuse.... I bought the truck as is and am only getting ready to put it on the road so I guess that's on indication how it was used. Rears are 3.70 with 18 speed
(11-22-2021 )Truckdriven Wrote: [ -> ]Yeah I hear you on the torque/abuse.... I bought the truck as is and am only getting ready to put it on the road so I guess that's on indication how it was used. Rears are 3.70 with 18 speed

3.70's are nice (with a set of low-pro 22'5's on it) for a highway truck that is only going to haul 80k lbs or less... if it is going to be used with higher applications than better rears are definitely needed.
Check it very well with a straight edge,
I just did mine at 800k on a 2012 Volvo with a CM2250. Make sure you do the rear motor mounts while you are in there. At 600k+ they probably need replaced. Also a good time to do clutch and flywheel.. mine were fine but I replaced them anyway as that is a TOUGH job on a Volvo… good luck.
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