4.3 in 71 getting 19 MPG?!?!? - The 1947 - Present Chevrolet & GMC Truck Message Board Network

Huck · 10-21-2005, 07:04 PM

Had a 91 full size with 4.3 and auto--got 21-mph hwy. My 2000 Z71 with 5.3 will get 21mph if you keep it under 70---even with the 373 gears. The 4.3 is an excellent motor but expensive for a rebuilt. Have not heard many raves about the inline. I personally have never had luck with an inline GM 6 going back 40 years. Keep in mind the 4.3 is a 350 less the last 2 cylinders. My 91 had adequate power for normal use and I was very pleased with it for 135000 miles.

10-21-2005, 07:04 PM	#27
Huck Senior Member Join Date: Jun 2001 Location: Shelbyville, KY Posts: 3,269	Re: 4.3 in 71 getting 19 MPG?!?!? Had a 91 full size with 4.3 and auto--got 21-mph hwy. My 2000 Z71 with 5.3 will get 21mph if you keep it under 70---even with the 373 gears. The 4.3 is an excellent motor but expensive for a rebuilt. Have not heard many raves about the inline. I personally have never had luck with an inline GM 6 going back 40 years. Keep in mind the 4.3 is a 350 less the last 2 cylinders. My 91 had adequate power for normal use and I was very pleased with it for 135000 miles.



Register or Log In To remove these advertisements.

Register or Log In To remove these advertisements.