Transmission: Downshift making noise

Discussion of the 5.7L-6.1L-6.4L HEMIs.

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2SLO4U
Posts: 58
Joined: Thu Jun 24, 2004 7:31 am
Location: Gainesville, FL
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Transmission: Downshift making noise

Post by 2SLO4U »

i have had this problem for a little while and i wanted to see if others were experiencing something similar.

when cruising around 50 to 60 mph under light throttle with overdirve engaged when i give it enough gas to downshift out of overdrive to pass someone the engine picks up third gear (or even second) and it makes a disturbing sound. i can only liken the sound to a moped with baseball cards in the spokes or the catalytic converter has something rattling around in it. i know this is not normal and it is not very consistent occurence except during the scenario described above. it does do it often enough that it is somewhat concerning to me. it shifts fine and hooks fairly well.

this truck has less than 20,000 miles on it and is a BONE stock 2003 QC Laramie with 20's and 3.91 gears. i plan on keeping it stock and we only put about 4,000 to 6,000 miles on it a year. we bought it used with 11,000 miles on it and it still has the warranty until december 2006. any advice or shared experience would be appreciated.
2003 1500 HEMI 2WD Laramie
1964 D100 426W High Performance Package
fletchkirk
Posts: 1
Joined: Thu Oct 13, 2005 11:08 pm
Location: Phoenix, AZ

Transmission down shifting noise

Post by fletchkirk »

Hi, I am new to this forum. I have a 2004 QC1500 5.7 Hemi 5sp. auto 2wd 3.55 posi with the factory 20's. I pull a single axle trailer under 2,000 lbs. My complaint is that when I give it a little throttle to pull a slight grade the trans will jump from 3100 rpm to 4900 rpm in one down shift. Its just seems too agressive and causes a bad decrease in fuel mileage. I wish that the profile in the PCM would require a lot more increase in TPS before making the big down shift. It should only down shift one ratio at a time when it receives a small increase in TPS input. I never tow with the tow mode on. That just makes the up-shifts hang longer. That also adds to the poor MPG. Yes I do travel at high speed. I cover 11 states in my work. 56,000 plus miles in 13 months. Alot of it at 80-85 mph. Time is money.
Does anyone know of a fix? The TSB's do not address this issue and none of the aftermarket reprogramers address this also. Note that none of the reprogramers address anything with the Trans after 2003 model year.
:-?
Kirk P. Fletcher
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