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First Impressions of ATT

I did my research guys :thumbsup: I pulled the pulley off the old one and swapped it out on the new one as soon as I pulled it out of the box. It's been on there for almost a year also, so I'm used to seeing the RPMs even if they were the wrong ones.
 
I have also noticed lower rpms while cruising in OD - as long as I don't drive the truck like if I just stole it - after the install of the ATT on my previous truck. Can't remember if that was 400 less, might be around 200 less.

Could it be because of a better/higher torque delivered with ATT? So the 4L80E OD stays locked at lower RPMs?
Or is it related to the fact that boost is low at cruise speed?
 
Measuring diesel pulley top of belt grooves is 62mm. Gassers are 57mm. Diesel alt pulleys are bigger and turn the alternator slower. So the lower RPM reading is the correct pulley. Inaccurate RPM is useless as it varies 2-400 RPM over the range.

This makes no sense as we have two batteries and lower RPM range over a gas engine. Less demand from ign coil maybe?
 
RPM won't change unless gearing, tires.....ect are changed. It "might" take less pedal to get to the same speed as before, but if you are at same speed in same gear as before the RPM will be the same after.
 
More precisely, what I mean is that it did seem to me that, once OD engaged after I reach the desired speed, I was able to release the accelerator pedal, decrease my speed (and so rpms) with the OD still engaged at lower rpms.

I've never been able to explain why, so I'm just guessing better torque :dunno:
 
I'm not sure guys, I think it was mostly because I had to keep on the throttle more to keep it at speed. You have to remember I have an extra 2500-3000lbs in the bed at all times and it was kind of a challenge at times just to cruise around at 55-60 without keeping my foot on the go pedal :thumbsup:
 
with more go pedal and only running 55-60 I bet the TC wasn't locking. PCM probably thought you were going up a hill LOL
 
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