8.1 liter gm startup engine noise
10-04-2006 | 12:19 PM
#13
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Re: 8.1 liter gm startup engine noise
The coefficient of thermal expansion of cast hypereutectic aluminum (piston) is nearly twice the CTE of Cast Iron (block). When the engine is cold the piston ring clearance is two or more times what it should be when all warmed up. Couple that with the oil drain issue and it's going to make for a noisy startup. (My Ford V-10 did the same thing for about 30 seconds).
The question "is this normal," can only be answered with a yes, because all engines with this combination will do it to some degree and there's nothing that can be done. Is it bad?.....Who knows, but it's certainly not desirable.
The question "is this normal," can only be answered with a yes, because all engines with this combination will do it to some degree and there's nothing that can be done. Is it bad?.....Who knows, but it's certainly not desirable.
Last edited by CigDaze; 10-04-2006 at 12:34 PM.
10-04-2006 | 03:47 PM
#15
never trade luck for skil
Joined: Dec 2004
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From: San Diego, CA
Re: 8.1 liter gm startup engine noise
Originally Posted by wannabe
How do I meet the girl in the Avatar? 
10-04-2006 | 04:34 PM
#16
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Re: 8.1 liter gm startup engine noise
I put 46000 miles on my 2500 Avalanche, 2002 model with the 8.1. Mine never had any issues. It made a little racket at startup if it sat for longer than a week. I used strickly Mobil1 Synthetic and Lucas Oil Treatment.
10-05-2006 | 04:37 PM
#17
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From: Troy, Mich
Re: 8.1 liter gm startup engine noise
Originally Posted by offshore whore
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Good.. She's available- tell her I got a twelve -incher and lots of cash. Hope she likes suprises!
10-06-2006 | 10:19 AM
#19
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From: 29°50'49.74"N 95° 5'17.55"W.......TEXAS
Re: 8.1 liter gm startup engine noise
Originally Posted by johnnyboatman
some noise comes from the allison trans, if you ever listen close they have a rattle when first starting .
10-06-2006 | 10:43 AM
#20
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Re: 8.1 liter gm startup engine noise
Originally Posted by Wobble
I didnt know that you could get an Allison with a gas motor.
The 6.0L Gas engine came with the M32 (aka 4L85E) 4spd Auto. The M32 tranny was mated to the 8.1L in the 2500 Suburban/Yukon XL/Avalanche. Also found in the AWD versions of the Denali and the Escalades with the HO 6.0L; as well as the Sierra Denali with the AWD/AWS.
Last edited by Sydwayz; 10-06-2006 at 10:53 AM.
