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Better fuel economy with front output shaft (drive shaft) removed?

1192 Views 3 Replies 2 Participants Last post by  K15 Blazer Guy, 
Family Force 6
Riddle me this..

Getting ready to do 1200 miles on my 99 suburban with a NP246 auto-trac transfer case. I have the front drives shaft out now to get a u-joint replaced which got me to thinking. Would I see an increase in fuel economy if I left it out for the trip? The front output shaft spins constantly with the auto-trac transfer case, however I understand that there is no "power" being sent to the front wheels.

And yes, I'm doing most of the basic tune-up stuff right now that will REALLY make a difference, including:

New O2 sensors
New distributor cap/rotor
New air filter
Oil change
Seafoam throttlebody treatment
A/C fixed (yea for A/C!)

I can't think of any reason why I would need to have it in.
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K15 Blazer Guy
I would say no... plus it could mess with the transfer case... your allowed to shift into 4WD up to 25mph and if the front input/output is not spinning like it should be the computer could have a fit

best way to boost your MPG is an intake, and delete the mechanical fan for a good electric one.
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K15 Blazer Guy
I got a simple K&N intake. not the big tube 57 series.

Vehicle Car Auto part Motor vehicle Engine

this works best for my old engine. i gained HP and MPG (one more than the other depending on how i drive)
also lets me hear the engine better too.

as for the fan

http://www.gmtruckclub.com/forum/showthread.php/124193-electric-fan-mechanical-replacement/page3

I put mine in, in an afternoon.
with a 160 thermostat it runs perfect, even with the noticeable gap between the fan and the stock shroud.
i may cut an inner tube to fill it later though.... but for now, its fine. i don't even run it when im at highway speeds

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