"Houston - we have a major malfunction..."

[markrinker]

Well I sensed something was changing under the hood. There was a certain 'growl' that wasn't diesel rattle and wasn't characteristic for this otherwise quiet 124K motor. I had checked the oil and transmission fluids more often in recent trips. I found my eyes scanning the gauges frequently...good oil pressure...normal temp...hmmmmm.

Today it happened. I am sure its a broken crankshaft. One minute I was singing along at 60MPH and the next it sounded like my motor just ate a 5 gallon pail of shrapnel. Not the 'whap whap whap' of a single rod cap come loose...an instantaneous, loud and constant growl from the firewall like 500 bad brake shoes metal on metal.

ARRRRGGGGGGGGGGGGHHHHHHHHHHHH!!!

But...this is a great time to build a new MONSTER, right? All the good parts...build it for the next decade of plowing and towing...check out this as a starting point...whaddya think???

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&category=33615&item=2469943505

[EWC]

I'm not too sure about the oil spray blocks .

[britannic]

If you have an auto, did you rule out torque convertor failure - they can sound similar to your description?

[tanker]

This happened to me two years ago, but I lost power, and it sounded like a valve tap, or broken push rod. I drove it almost another 100 miles before loading it on a flat bed. As mentioned above, it could be something else, lets hope so. Check it out first. Is coolant in the oil? Drain the oil, and what do you see? Pull the oil pan down, what do you see? :eek: Investigate first. It sure does not sound good. :confused:

[gmctd]

Also sounds like a torque convertor\flywheel bolt came loose.

[markrinker]

I towed it to a local repair shop where I trade plowing for repairs. I'll have them pull the inspection cover first and eliminate the 'torque converter theory' first. It had crossed my mind as a possibility - as this is the truck that I wrote of last week that had some random slip when starting out from a dead stop.

I certainly hope thats all it is...

[tom.mcinerney]

Hopefully just converter.
If not I want to emphasize what EWC mentioned. My understanding is the 97/98 early piston-spray blocks were worst for cracking, because had largest spray holes, weakening webs where were already somewhat failure-prone. Better earlier or later blocks. The price is right, though--a free engine with the trans!

[markrinker]

Confirmed this morning - crankshaft is broken.

[whatnot]

Was the balancer ok?

[Spindrift]

Mark,

It looks like the eBay truck gave/received a serious kiss. Front end gone, turbo appears to be gone/removed, silencer broken, etc.

How would you determine whether or not the drive line hasn't been adversely effected in some way?

Wish you well on your replacement.

[markrinker]

Spindrift - I agree its a risky proposition buying used. However $6,500 for a drop-in remanufactured 6.5 with warranty is more than the truck is worth, and would be a better downpayment on a new high mile Duramax.

As luck would have it, the better of the two 1994 trucks chassis-wise is the truck thats down. If it were the other, I'd part the truck and move on...

From a compatibility point of view - what year engine/trans combos are 'plug-compatible' with my electronics? 1994 - 2000? Does the 4L80E transmission have to be from a 4WD vehicle, or would a 2WD version suffice?

Also - I replaced the water pump, fan and fan clutch last fall. At that time, the harmonic balancer appeared to be in fine shape. In retrospect, I wish I had replaced it, just to be on the safe side. Who knows...

[ 03-29-2004, 02:03 PM: Message edited by: Mark Rinker ]

[Uncle Wally]

Mark,

There are some differences between the 4x4 and 2x4 trans. Output shaft being one. A second speed sensor being the other. Along with a possible list of other things that I am not sure about.

Waldo