Anyone own a vehicle with this engine? Eats gas of course, but is there anything inherently bad with this engine?
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Thanks for the replies all.
So, Im looking at this engine as an option in the next truck I purchase. The Excursion has too many gremlins piling up and frankly, I have no desire to put more money into it. The Triton series of engines isnt bad, but I have zero desire to dive into them for major repairs. In this realm, the GM LS and this here 8.1 are superior.
I dont want a new truck payment, and I want something thats simple and reliable. Im open to a 2003-2006 5.9 Cummins Ram, but Ive only found a handful of them.
I have a 2004 GMC Sierra 2500 HD with the 8.1L and the Allison 5 Speed auto. I got the truck in 2013 with 91K on it and it now has 118K. The trucks is a beast. I only plow the driveway, go to the dump, and tow my car with it, hence it's low mileage. The truck tows my 20' trailer with my hellcat on it with no issues. It's stock besides shorty headers, intake and catback. They like to drink oil. Between oil changes I usually put a quart of oil in it, but that's pretty common from what I've read. It's a shame they don't offer a motor like this anymore.
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That's a good looking truck, Ray. 27K miles over the past 8 years is definitely low miles. I assume it's primary duty is to tow your Hellcat.I have a 2004 GMC Sierra 2500 HD with the 8.1L and the Allison 5 Speed auto. I got the truck in 2013 with 91K on it and it now has 118K. The trucks is a beast. I only plow the driveway, go to the dump, and tow my car with it, hence it's low mileage. The truck tows my 20' trailer with my hellcat on it with no issues. It's stock besides shorty headers, intake and catback. They like to drink oil. Between oil changes I usually put a quart of oil in it, but that's pretty common from what I've read. It's a shame they don't offer a motor like this anymore.
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Is that 12.5 your average city/highway? If so, thats already a 3.5 average improvement over my Excursions V10 lol.I just bought an immaculate 01 2500HD 8.1. My two checked fill-ups got me 12.5mpg. 3.73 gears. Keep in mind the factory tire was 245/75/16. Even a 265/75/16 is going to throw your mileage/economy off - 5%.
They have oil consumption issues because of the intake manifold design and how oil vapor is sucked in. Supposedly the best fix is a lower thermostat.
The Allison trans in the truck is really nice. I wouldn't want to own an 8.1 behind a 4l80 with that sucky long first gear, which is what every 2500 suburban/Yukon used. Probably why they seem to have worse fuel economy.
I had a same year 6.0 2500 and it felt slow to me from a dig. The 8.1 roasts tires.
Is that 12.5 your average city/highway? If so, thats already a 3.5 average improvement over my Excursions V10 lol.