02 Rattling.

[DMAXTODD]

Anyone notice a slight pinging sound on light to mid excelleration through all gears around 1800-2000 rpm.It reminds me of prignition pinging on an old S-10 that I had years back. I am pretty sure the pilot injection seems to work properly at the higher rpm's,that noise Sounds like my 01 except for this pinging which the 01 did not do. should I worry? my first tank was 15.6 Mpg.

[TEXASTOUGHDMAX]

DMAXTODD,

I'm glad you brought this subject up. My '02 does the same thing. I bought it used about a month ago with 54,000 miles on it, so I dont't know alot about its' growing-up days. Haven't had a chance to talk to the stealer about. Maybe the more experienced guys can enlighten us.

[Bullseye54]

Mine is a 2003 & it is in the shop for that right now.At about 2200 on cruise & you go over a slight rise where it has to decellerate slightly it rattles,it also has a surge when towing 10000lbs at that speed.I've got some computer problems they think might be related.

[BigLakeDMAX]

My '02 has done this since new. Has 18k now. Almost sounds like an exhaust leak at times. It also becomes a steady light tapping sound at idle when warmed up. Have had three different techs check it - two said it was just normal diesel sounds (just listened and test drove, did no diagnostics). Last one was able to get the sound to change when he altered fuel rail pressure with his Tech II. Could find no specific cause of it, however. Injectors tested OK, however he said one was "iffy." Truck gets 19mpg highway, 16 - 18 daily driving, 10 - 14 towing, 0 - 60 in 8.4 - 8.6 secs., so whatever it is does not seem to affect driveability.

Tech's advice was to worry about the big sounds and driveability problems. Still annoys me, though.

Love to know if anyone finds an answer to this.

[hoot]

Search "tick" to see if it's waht you're talking about.

[TEXASTOUGHDMAX]

DMAXTODD,

Do you feel a "surge" of power when you hear the noise? Does it shift or does the torque converter lock up and then the noise go away? Mine sounds like it loses its "quietness" ability when it does it. Only lasts about a second. Just wondering if we are talking about the same noise.

[Bullseye54]

TEXASTOUGHHDMAX

My rattling is like yours.I just picked it up from the dealer.I got the ol' thats normal.I convince him that we need to go for a ride,& I get it to realy rattle & then surge or drop rpms & he said all diesels do that.Also have a steeltec that won't ballance & rattles the dash that he said is because it's a hard compound.I can't shoot him so I guess I look for another dealer.

[TEXASTOUGHDMAX]

Bullseye54

I plan on taking mine back up to Austin (where I bought it) in a couple of weeks and let them look at it. Can't get there sooner due to taking the family to Florida next week for vacation (taking the wifes '99 Chev Sub. 2500LS due to more room).
The techs at the GM dealers in my area have very little knowledge of the D/A. They don't even keep the minimum stock of parts on hand! I was looking for a fan belt and the parts guy told me he had to order it and it was $57! I told him I would get back with him and went home and found the part at GMPartsDirect.com for $35! Same thing goes for the rear U-joint I had to replace. GM Stealer: $94, GMPartsDirect: $65. Sorry, I'm rambling.......

[dieselburb]

Dmaxtodd, I think we have the same sound. Mine's an '02 and just turned 35,000. Shed's had it since birth and I was really worried about a failing injector. Turns out, injectors tested fine, actually really good, but that rattle is still there in that narrow rpm range: almost like a loose rocker arm. I think some guys may be confusing this with their pilot injection, the power surge and all, but just as you, I notice no power difference, no smoke, no driveability issues, just an annoying rattle. I did take the mechanic for a ride and he said he'd been in others that make the same noise, but nobody's really had any complaints about it other than it's annoying. Oh, well. Rattle on.

[DMAXTODD]

Well with the second tank down and I am up to 16.8 mpg,so I guess the rattle,tap,whatever does not affect mileage anyway. I was even towing 5,000lbs. some of those miles, so I am pretty happy with the mileage. The sound some of you are discribing sounds like mine, I thought it was quieter today but I had the windows down all day,windows up tonight and its back. The noise is annoying and makes you think something is not mechanically sound?.. My new truck does have the Idle TICK very loud also, much worse than 01..a coincedence?
But its running strong so I will keep rolling for now and figure it out later.Did any of you that have the rattle on the 02 have an 01? My 01 was very well behaved except for a idle lope that never went away, never made a weird rattle though except towing 12,000lbs pilot injection noise., Oh well enough worrying for tonight.

[DMAXTODD]

Dieselburb,
Good explianation,
It does sound like a loose rocker,or something loose somewhere in the motor. I know its not, but the way it sounds if it was a gasser I would be worried(I know diesel make more noises. Maybe I just need to get my 4' pipe on this new truck so that I don't hear it...

[DMAXTODD]

Texastoughdmax,
It does not surge or shift or anything. The motor is overall louder than my 01. First at Idle there is the famous TICK but alot louder than my old truck,starting to accelerate through the gears lightly it just taps or rattles lightly and is not totally consistent at a certain rpm,but mostly at 1800 to 2,000,noticable especially when easing on the throttle to maintain speed in O/D at 1800>2,000 or so rpm.. I don't know if it taps at full trottle because the exhaust is louder. It just does not sound very good.

[jbplock]

DieselBurb,
You described exactly what my 03 does. It used to worry me until I talked to some other Dmax owners who described the same thing. Now it just annoys me, so I just crank up the CD player and it's gone. I notice it most from 1500-1800 RPM's. At 2000-2100 rpms it's pretty smooth. Above 2200-2300, I understand that that the pilot injection turns off and it will start to rattle. I drive pretty conservatively so I never get the RPMs that high. (I would if I was towing a hill, but I sold my 5ver).
smile.gif

[Husker Fan]

I've noticed a sound that is similar to what you are describing. But to me, it sounds normal. If it's like mine, it sound kind of cool.

[ 06-06-2003, 11:55 AM: Message edited by: Husker Fan ]