Bump or Thump After Shutting Down

[Shelby Griggs]

I have noticed a few times, twice today, what sounds/feels like a bump/thump/thud in the truck after shutting off the engine, but before I exited. Don't know how else to describe. A burp in the AC system? Something with the accumulator on the master cylinder?

Anyone else ever experience anything like this?

Need some sleuthing help to solve this mystery.

Shelby

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2001. 5 2500 QC LB 4WD, ETH, DEE, 3. 54 gears, Laramie SLT, Camper Special, Trailer Tow, Travel Convenience Group, Power Driver Seat, Alarm System, Remote Keyless Entry, Fog Lamps, Cab Clearance Lamps, HD Transfer Case, Bright White with a Gray Interior. Built 09-15-00, took delivery on 10-06-00, 1749 miles as of 11-25-00. Custom aluminum work body / flat bed. Coming soon: E-Brake and gauges.

 

[rogerblind]

I've never noticed it at normal shut-off, but I have noticed a distinct thump/bump if I bump the starter and wait until the lift pump stops running (as after changing fuel filter). I've always thought it to be curious, but figured it was just part of the "beast. "

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Y2K 2500 4X4 LB QC Auto Trans

 

[Big MAK]

Maybe you forgot to set the brake and rolled over a cat looking for a warm place to sleep? Check under the wheels.

(it's been a long week... )

Running your defrost? Atleast I think it's the defrost... maybe it's the heater. At any rate, I get a thump from the vent area at shutdown and it's the one of those redirect vanes in the ventilation releasing at poweroff.


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Big MAK
98. 5 ISB 5spd 4x4 Quad Cab 3500, 275s and Original PowerMax
A "WARRANTY FREE" ZONE
https://www.turbodieseltrucks.com

 

[Shelby Griggs]

Mark,

It could be in the heater system, I have been shutting down with the defrost active. That seems to keep the windscreen a little bit more frost free while plugged in. I have not heard the noise since I started this thread, been several hundred miles since then. I will keep my ears tuned and post anymore information I come up with.

Shelby

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2001. 5 2500 QC LB 4WD, ETH, DEE, 3. 54 gears, Laramie SLT, Camper Special, Trailer Tow, Travel Convenience Group, Power Driver Seat, Alarm System, Remote Keyless Entry, Fog Lamps, Cab Clearance Lamps, HD Transfer Case, Bright White with a Gray Interior. Built 09-15-00, took delivery on 10-06-00, 1749 miles as of 11-25-00. Custom aluminum work body / flat bed. Coming soon: E-Brake and gauges.

 

[KWIKKURT]

Shelby... I have heard the same sound in my Truck. . I'm sure my thump is a door in the air cond / heater system. . After you shut of the engine you lose vacuum in the system -after a few seconds the spring loaded door thumps closed. .

Or it might be a next door neighbor hitting his head on a tree trunk for buying brand F or brand C . #ad


Kwikkurt

[This message has been edited by KWIKKURT (edited 12-30-2000). ]

 

[mbrolin]

It could be your heater/defrost baffle. Its possible your vacuum system bleeds down quite fast. When I start mine in the morning I can here the heater/defrost baffle thump into place a the vaccum builds.

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2001 HO 6spd,Quad cab,LWB,4x4,Flame Red,all options except for leather,Westin Brushguard/Push bar,Painless wiring,Radio Shack CB( so what it works},my own designed CB mount,Smittybuilt nerf bars,NW Custom rocker covers,Custom built stainless rocker light bars(more to come)