i was towing about 5k on a flatbed trailer and was sitting at a light before being rearended by an suv. only damage i could see was the trailer tailgate of course and the hitch/bumper were pushed down a couple inches (loosened bolts, repositioned bumper/hitch and retightened bolts, fixed that). after the accident i started noticing a new engine noise that seems to be coming from the drivers side of the engine and increases as rpm increases. it sounds kind of like a loud valvtrain noise on a car engine. it does it in all gears at all rpms and is louder when the engine is under load. at first i thought it was the injection but when i listen w/ a stethascope there is also a very noticable similar sound coming from the oil pan (bearings). i cant see how being hit in the rear could have damaged the engine, anyone have any ideas before i take it to the dealer?

 

many years ago, i had a similar experience with an old 1971 Pontiac LeMans with a big block V8. The sound started getting progressively worse, and we tore the motor down to find out that it had a cracked crankshaft!!!! But it was still running because of where the crank was cracked, the main bearing caps were kinda holding it all together for a while. I sincerely hope this isnt the case with your CTD, as i would imagine the CTD crank is 3X the size and strength of a Pontiac Big Block. Anyway, i am interested to hear what you (or the dealer) determine to be the problem.

 

You might check the engine mounts. The sudden impact could have caused them to shift, olthough it seems unlikely.

 

Maybe exhaust got bent? Heat shield or something simple probably.

 

i checked all the engine mounts and the exhaust is fine, no leaks. the noise is definately coming from the motor. the bottom end is very noisy, but all diesels probably are. i am going to drain the oil to see if theres anything noticable. im starting to wonder if it could be an injector. i never had one go bad, the truck only has 10k miles on it. everyone has described injector ticking kind of like this sound but i still cant tell if its coming from the bottom or top of the engine. what exactly does a bad or cracked injector sound like and what would be some other signs of a bad injector? this noise is noticable at idle as well as any other rpm and alot more noticable while towing under load. its like a ticking or slight knocking sound and it increases steady w/ rpm.

 

you may have damaged the thrust bearing on the crank if the driveline is subjected to a severe shock straight ahead. contact your ins company and let them know its going to the dealer because of this accident.

 

that sounds expensive. i was thinking about the shock to the driveline but i figured since the hitch/frame was basically hit, it would have moved the engine forward w/ the frame while the rear and driveshaft stayed in place so i didnt think it would have jammed into the engine. am i making any sense at all?

 

oh yeah, and i havent even contacted the insurance company yet because the lady that hit me said she didnt have her insurance info w/ her and offered to pay for the damage. so she ended up giving me a check to pay for the trailer tailgate. i dont even know if insurance would cover it now?? i am hoping warranty will cover anything wrong w/ it.

 

if the rear axle moved foward, it shoves the driveshaft into the tcase deeper. if the shaft spines bottom out on the tcase output shaft, it transmits the shock foward. i know that there is plenty of room between torque converter and trans input shaft to allow some fore and aft movement, but a severe shock will take up any room, and shove the crank forward, etc. the thrust bearing is the upper bearing on the 6th journal(start at the front when counting)

 

i was sitting still w/ my foot on the brake so wouldnt the axles stay put while the frame, engine and trans move forward. if anything i would think the tcase may have been pulled away from the driveshaft a bit. but the front driveshaft could have been jammed into the tcase i guess...what would that do?

 

Get an oil sample and send to blackstone labs. If there is a crack inside the motor there would be some detectable metals.

 

I'll bet it is in the transmission to engine bolt up. The noise is coming from the front pump on the transmission. Your transmission will go out in short order. Then it may start up again after you install a new transmission. Then the cycle will repeat itself.
We had this happen to a 2001 Dodge pickup my son drove. We had 5 transmissions installed under the extended 75000 mile warranty.
The transmission may be slightly misaligned with the engine due to the rear end hit. There is a tolerance for some variance in lining them up from the factory. Yours may have been at the extreme and the rear end hit put it out of tolerance.
That was the probable cause of my son's transmissions being replaced so often. He'd been hit in the rear. It was repaired and the transmission went out in less than 5,000 miles after that.
He'd been hit low, below the bumper which had been lifted up. If he'd been hit in the tail gate, the frame wouldn't have been bent.
Dodge frames are not as strong as you think they are.

 

i will get under the truck and listen to the trans, but the noise stays the same in neutral as well and still increases while reving the engine even when in neutral. the noise sounds like it is definately in the rotating assembly because of how consistant it is w/ rpm.

i remember on my ford which was a 6spd trans, when i was driving and took my foot off the gas pedal the injection noise would stop until the rpms went down to idle. is the injection noise also supposed to stop on my cummins w/ auto 48re? because now i notice when i take my foot off the gas pedal the noise stays the same and slowly decreases as rpm decreases.

 

well i got by the dealer today and one of the service writers went for a ride w/ me. he noticed the tapping sound and said not to worry about it until it gets louder and then bring it in. he also told me that the valves should be adjusted every 50k but as far as i know the book says around115k. he said thats way too long. anyway, it sounds like he thinks its a valvetrain noise. he said that every diesel gets louder after its broken in and every diesel has its own sound, not to worry about it unless it gets very loud/noticable. oh well, i guess i will drive it until something breaks. it seems like it is now most noticable after letting off the throttle.

 

My money is with dodgezilla, Even the 855,s will break the thrust bearings from backing under a trailer & hitting the kingpin hard causing crankshaft back lash, I,d drop the pan & check. cheap peace of mind