Well, this symptom is kind of hard to describe, as I'm sure all rattles in the front end of a diesel motor are. I have been driving about 140 miles back and forth from Kansas City to Rolla, MO, and everytime after 90 miles or so and I'm slowing down going through all of the smaller towns my truck has a rattle in the front part of the motor. When I get back up to speed 60-70mph it goes away. It seems like it only makes the noise when I'm driving for over an hour at highway speeds. The best way to describe the noise is sort of a chain rattle. Like when you are riding a 10 speed bicycle and you switch gears, it sort of sounds like that. I have read numerous posts on timing rattle, injector ratttle, and I'm just kind of stumped because it doesn't really seem to have any of those symptoms. Only when you are slowing down from highway speeds to 35-45mph. I thought maybe the fan clutch, but wouldn't it rattle when idleing if it was that? Also, I have no power loss whatsoever. I thought maybe a pulley? All of those seem to be tight and good to go. Any help would be greatly appreciated. This also happened when I was driving the truck back from CA once, but went away and never happened again. I was also reading something about the Cp3 timing or something to that effect? Anyone know anything about that?

 

Did you try running it without the Edge ?

 

I tried it right after it happened without the Edge, but tomorrow I'm going to try to run it the whole way on stock and see what happens. When I tried right after it happened without the edge it still did the same thing.

 

Hopefully someone with such experience chimes in.
Keep us posted
Good Luck

 

Ok, so the last couple of days I have really been trying to narrow this down. So, I put my edge on level 6 and got on it. I'm only building 28 psi in boost, I haven't really got on my truck in a while so maybe that's why I didn't really notice anything. I believe when I first got the edge I would build like 40 psi easily. Looking back I realize that my truck has been kind of doggy. So, I'm thinking this rattle could be my turbo? I'm going to pull my intake off tomorrow and check the shaft for play. Also, when I was driving about 60 down the road today and edge on level 6 tried to build boost and it just kind of popped and the edge let off. I just checked for loose connections for boost leaks everything seemed tight but that was just a quick visual. All the clamps seemed good to go going to the intercooler. I'm getting ready to try to find some posts on turbos taking a sh**. I just figured I would see if anyone else wanted to put their .02 in. Thanks

 

I also want to add when I put the edge on lvl6 and hit it rom 60 or so without the transmission downshifting I felt a shutter. I'm not sure what a turbo shutter feels like, but...........I originally thought it was my transmission, but now after reading up on this I kind of think I'm going to find something wrong with my turbo tomorrow. No comments anyone? LOL I figured someone would be all over this. Thanks again

 

I have never heard of a turbo shutter, and I HIGHLY doubt the problem is with your turbo. The shudder could be the torque converter or a driveline issue. (Like a bad u-joint) The timing rattle, does it sound like nailing? Do you have an after market fuel delivery pump on your truck?

 

Yeah I have the Airdog II 165. I'm open for all options here. I was thinking it could be my Cp3 going bad. I guess that could be causing the rattle. The rattling only happens when I decel, it seems to go away when I give it gas and accelerate. I guess that could cause my turbo to not build boost? I'm not sure.............The only thing is I can only hear this rattle when I'm driving. When it is in park and you rev the engine you can't hear anything. It runs like a top.

 

Well, I'm just about 100% sure I found the rattling, clattering, and chain sounding problem! The U-joints that connect to my transfer case are freakin shot! Probably the worst U-joints I have ever seen. I got under my truck today and started grabbing things and finally found it. I didn't even think the U-joints on the shaft could make a sound that to me sounded like it was coming from the front of the engine. I haven't changed them yet, but I'm pretty sure that is that problem. The boost issue not sue yet, but two problems at once can get a guy pretty confused in what is going on!!

 

HYVYTRKMECH hit it right on the money with the U-joint suggestion! LOL Thanks for the help.

 

Did you figure out the boost issue? Fuel starvation will cause boost to be lower than normal... Clogged filter?

 

Well, the edge was the problem with the boost. I guess its messed up somehow. Now it surges really bad on lvl 6, and all the other levels, just not as noticeable on the lower levels. I tried my buddies smarty s-06 last night and holy cow! The smarty goes to 40 psi and sticks like cement, love that thing found one for sale 40 miles away and went and bought it last night. I kept the edge on for now for the gauges. I'm definitley a SMARTY FAN!! I still think my edge has it beat on the top end but you can't even compare on the lower end. Also, my truck just seems to run better overall. VERY PLEASED!! The edge will probably never get utilized in my truck ever again. I guess I definitely have a reason to get that tranny I have been waiting on. Don't think it will hold up too much longer after I get done playing with this thing! Can't wait............ Thanks for all the help guys.