What did you do to your NNBS GMT900 Tahoe/Yukon Today?

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Geoffsfas10

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Well this is weird...today it got cold and rained. Drove tahoe to work, everything was fine.

Went to leave work, acted like dead battery, one crank then gave up. Pulled key, tried again, it tried to start but the timing of the starter was real weird. Then it turned real quick and started up. Was fine once running. Drove it home and parked it, started right back up.

Went to go on an errand a couple hours later, no crank start, pull key, multi-meter on battery..12.2V...tried again and started right up.

Went to Autozone, did battery check, 96& charge and cranking amps were fine. Started fine there, went to store, started fine there.

Texting the shop who did all the work, they think I have a weird ground somewhere from everything being apart, and possibly the rain was effecting it. It was after hours, so we're going to work out troubleshooting it there tomorrow. Will be interesting to see if it starts no issue in the morning once its dried up.
 

Geotrash

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Both my 2011 and 2012 6.2l had AFM and also had sticker on MC Reservoir.

The engine in your pics doesn't, so like said above, it's either been replaced with one that doesn't or someone did an AFM delete on it.

The 8th digit of the vehicles VIN will give you the engine code the vehicle left the factory with
 

tungsten

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Both my 2011 and 2012 6.2l had AFM and also had sticker on MC Reservoir.

The engine in your pics doesn't, so like said above, it's either been replaced with one that doesn't or someone did an AFM delete on it.

The 8th digit of the vehicles VIN will give you the engine code the vehicle left the factory with
Thanks,L9H vin is "2" Summit website says non AFM.Haven't looked anywhere else though.
 

Geotrash

Dave
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Sticker on the brake rez says AFM ? Twice now Ive seen this. Both engines said to be stock L9H.Weird.
Sorry, I should have been more clear. I meant that AFM was being built into the 6.2 beginning in 2009 for the 2010 model year. AFM came with the L94 version of the 6.2. I think the AFM sticker is unrelated.
 

pwtr02ss

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I really doubt it. Jacking up the line pressure is a very rookie move. I can't see BB doing this. A good tune should actually extend the life of the trans since it would reduce the shift confusion, slip, unnecessary shifts and general slop the factory has programmed in to make it soft and comfy.
I know we're talking about 6l but I still bump the line pressure on the 4l60s if I do any trans tuning. Not across the board but above 50%, incrementally.
 
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