Rusty c
Newbie
Just bought a 97 3500 dually that originally had a 7.4 that was taken out I have a 5.7 out of a 98 or a 8.1 out of a 02 avalanche that I would like to put in it witch would be the easiest swap to the 5.7 or the 8.1
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100% agree with syndicate. If you have the wiring harness and computer from the 8.1, that's what I would do.Just bought a 97 3500 dually that originally had a 7.4 that was taken out I have a 5.7 out of a 98 or a 8.1 out of a 02 avalanche that I would like to put in it witch would be the easiest swap to the 5.7 or the 8.1
Depends on whether you are towing anything. I bet the 5.7 gets better mileage around town unloaded, and worse mileage towing a heavy load.Hey now, don't hate on a 5.7 Vortec in a 1 ton, mine goes plenty good when you get your foot in it. The issue now is with stopping it....
And the small block doesn't want to stop at every other gas station lolol....
My 350 towed well especially once I ditched the 3.73 gear. 12,500 GCVW. Still netted 11-12 mpg on the flats and around 10 in the mountains. I did have tri-y headers and a small cam in it though. With 5.13 gears it would go down the road at 70 mph at 2,800 rpm in overdrive. I was getting ~18 mpg empty with the 5.13s. I put the 3.73 gear back in with the 383 (took about 2 hours to swap the whole rear end). I tow in 3rd at about 2,750 rpm @ 70 now. Running solo its at 2,100 @ 70 and 19+ mpg. With fuel costs being what they are, I slowed down to ~60 mph on my last trip with the travel trailer. Over 700 miles it got nearly 14 mpg. My travel trailer and van have the aerodynamics of a brick and about the drag of hauling an open parachute behind me so slow and steady pays back woth less time spent at the pumps.Depends on whether you are towing anything. I bet the 5.7 gets better mileage around town unloaded, and worse mileage towing a heavy load.
You mean two axle trailer, tandem, not duals on single axle right? I'm just trying to imagine your burb towing ....Probably so! My Burb never tows anything bigger than a 6x12 dual axle uhaul trailer, and the only way you know it's there is on hills, parking or stopping. The smaller 5x8 single axle tows even better. That's what I have towed, earlier this year,the last times I had a big enough show to go to, that I needed a trailer.
Yes the biggest trailer they have, 6x12, double axle. We pulled one, loaded, with the Burb, and also with our '06 Yukon XL Denali,6.0 and 4L65E. I like the smaller one better,5x8, because it's about the same height as the Burb. So less wind drag. Towed one to Austin and back in April, did well on the hills (and we kept the trans in D instead of OD).You mean two axle trailer, tandem, not duals on single axle right? I'm just trying to imagine your burb towing ....
Yes the biggest trailer they have, 6x12, double axle. We pulled one, loaded, with the Burb, and also with our '06 Yukon XL Denali,6.0 and 4L65E. I like the smaller one better,5x8, because it's about the same height as the Burb. So less wind drag. Towed one to Austin and back in April, did well on the hills (and we kept the trans in D instead of OD).