Whats THAT Noise???????

[Great White]

I was driving my truck up the Grapevine I-5 loaded with firewood, the hill is steep. I proceded to throttle up (75 MPH)and was running hard for couple of minutes when this "death rattle" burst from under the hood. Only thing I can say it sounded like is rod bearing the instant before it blows. I lifted off the throttle and the noise went away. I moderated the throttle, since then I have run the truck hard but not with a load on a grade where sustained high output was possible. The reason I present this topic is that Grsjms a fellow TDR member related a similar problem but in his it is repeatable.
I know there are some real Cummins thinkers so pony up. What was it?

------------------
2001. 5 2500 ETH/DEE 4x4,Patriot Blue over Silver,Camper pkg, Trailerpkg,3. 54LSD, Agate Leather,Stainless Smitty Bars,Tow hooks,Amsoil,Window Fix... ... ... Except snowplow!

 

[Bob Wagner]

My guess its the cooling fan. When that mother engages it makes alot of noise.

Grapevine is a nice pull which will engage the fan easily #ad

 

[Guest00]

Is it repeatable ????
Do you have gauges ?????
What was your egt ????
What was your water temp. ????

 

[fj40charles]

My truck did the exact same thing when I was towing through New Mexico up some very long grades in 5th gear about 2600 RPM's.

When I got off the gas, the really noisy sound went away. I think it was the radiator
fan engaging.

Charles

------------------
2000 QC 2500 4x4 LWB ETC/DEE, Anti-Spin, 3. 54, Trailer Tow, Camper Special, DD1's, PS boost module, PS high idle kit, PS steel idler pulley, Autometer boost and EGT gauges, Westin nerf bars, Rhino Liner
*************************
My Toy

1969 Toyota Land Cruiser FJ40
350 TBI, Turbo 400, ARB lockers front/rear, 4 wheel power disk brakes, 4. 88 ring/pinion, 3 speed transfer case, full roll cage, Warn 8274, MRT 36 bolt beadlocks with Super Swamper Boggers (16x35x15), Saginaw Power steering, custom bumpers/fenders/nerf bars/skid plate, GM tilt steering column, 6 point roll cage, RCI racing seats with 5 point harness. Conquered Tellico and going to Moab this May. Loves to be pulled behind the Dodge and pass the powerjokes going up hills.

 

[ReggieRam]

I'd be willing to bet that it was the cooling fan. The first time mine came on, climbing the Continental Divide @ 75 MPH, I almost had a heart attack. Loud as hell, pretty scary. Now I just try and keep things from getting so hot so I can hear my turbo more clearly.

------------------
2000 3500 QC 4x4, 6 Speed, 4:10, LSD, Raider cap, Carpet kit, Spray-in liner, K&N Filter. "OBNOXIOUS BEAST"

 

[Great White]

Well sounds like the fan was the culprit. Wow, it's really loud then? I will push it harder this summer. We have a trip planned to the North rim of the Grand Canyon with stops at Lake Powell and Yellowstone. That will heat her up for sure!

Jnutter: No gauges yet, I was curious about the 3 gauge pillar mount with the dual function SPA gauges. EGT Inlet/Outlet of turbo, Boost/Fuel pressure, Voltmeter/Ammeter. I don't know if these combinations are available but seems to me this would be the best combination.
Thanks Again, Rich

------------------
2001. 5 2500 ETH/DEE 4x4,Patriot Blue over Silver,Camper pkg, Trailerpkg,3. 54LSD, Agate Leather,Stainless Smitty Bars,Tow hooks,Amsoil,Window Fix... ... ... Except snowplow!

 

[Texas Diesel]

Definately NOT the cooling fan. Sounds mechanical, sorta reminds me of valve or lifter float. Truck is stock so temps not available. Happens everytime on WOT @ 2000RPM or higher.

------------------
2001. 5 SLT QC SB 4X4, 6 speed, HO, LSD, 241HD, 3. 54, camper special, power everything, trip thingy, REAL bumpers, green/silver, Nerf Bars, Vent Visors, trailer tow pkg

 

[SmokinJoe]

Originally posted by Bob Wagner:
My guess its the cooling fan. When that mother engages it makes alot of noise.

Mine runs all the time. Sounds like a blower is under the hood... or a high speed wind tunnel...

------------------
2001. 5 QC 2500 White Sport 4x4 LWB ETC 5-Speed Anti-Spin 3. 54 Trailer Tow 241HD SLT+ Tan Leather(Mad Cow Disease) LT265/75R16E ARE Z Series Cap Bedrug ICI Nerfbars

[This message has been edited by Smokin Joe (edited 05-17-2001). ]