For the last year or so I've noticed my engine has gotten louder at idle and at lower rpms. From reading through a couple hundred threads in the DTR archives it makes me think my timing might be the culprit. This is possible, since I've never ever had the timing set! Truck has 203,000 happy miles on it, and I still get over 20 mpg on the highway. On my last trip in June I got 21+ mpg with about 1,000 pounds of tools and fuel in the bed. That 21+ was on I-40 over a stretch of about 1200 miles.

I'm in L.A. and need to find a good Cummins 12V mechanic anyway, and I don't want to go to a Dodge dealer. I also could probably use return & supply hoses. Anybody know of a good Cummins mechanic in the L.A. area? There has GOTTA be a few.

What else could cause the engine to get louder? I checked out the exhaust--I couldn't find any holes or loose connections, and I still have the cat. All the exhaust manifold bolts are tight, and it is the stock exhaust manifold--uncracked as far as I can tell, unless the crack is in a really hard to see spot. The Pacbrake hasn't worked in awhile, but I don't think that's the problem.

 

This info was give to me by another DTR member. I have not contacted the shop, nor do I know anything about it, but it could be something to check out. John @ Diesel Performance Shop, Van Nuys, 818-786-0126. Good luck. If you use and like them, post it or PM me, I have been looking for a good mechanic for a long time.

 

It would also help to adjust your valves.

 

Thanks guys. I'll check out the place in Van Nuys, and set my valves.
How much does a shop charge to set the timing? And how much generally to change the supply and return hoses?

 

I just gave a quick read-through of the procedure to check and adjust the timing, and the article gives several reasons for adjusting the timing, including white smoke, low power... etc. I'm not having any of those problems. Engine runs fine, but it's making more noise that it ever did, and that bothers me. How likely is it that the timing is the culprit--I'd hate to part with the $150 or more that it takes to check and adjust the timing if that's not going to quieten things down somewhat.

It's weird--I LOVED the sound of my truck for the first 4-5 years I had it, but now it seems way louder at idle and low rpm's, and it's not just me--other people have mentioned the same thing. Comments anyone? Questions?

 

I went and talked to John today, at Diesel Perf. Shop in Van Nuys. He sounds like a decent and knowledgeable guy. I'll let you all know if this fixes my noise issues. Thanks!

 

What did he say the possible causes of the excess noise could be?

 

He said it was most likely the valves, and we'd start there and see.
I'm happy with that diagnosis, because everything else about the truck--mpg, power, etc. is fine.

 

I see your location is "Santa Monica, Ca., and St. Louis, Missouri"

Did you just go from CA to MO? If so, cetane of the CARB diesel is much higher than everywhere else. Lower cetane = more noise.

 

Really? Hey that's good news for me.