The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > 47 - Current classic GM Trucks > The 99-06 GMT800 Chevy and GMC Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 12-01-2005, 03:40 PM   #1
trinic
Registered User
 
trinic's Avatar
 
Join Date: Aug 2002
Location: Wide awake Wylie (North Texas)
Posts: 322
Chevy Engine Swap from 8.1 to ???

My brother owns a 2001 HD 2500 (non-4x4) with the 8.1 Liter engine, which is attached
to the Allison Trans. He asked me to look around to see if it were possible to
replace/swap the engine out of it with something more economical....basically, something
that doesn't SUCK-UP so much GAS! From my point of view, he probably won't gain much
out of it. He currently has about an 6-8 inch lift, 30+ tires, big heavy A** bumpers, etc.....
Either way, I'd like to give him a formal answer with a bit more knowledge than I have. If it's
possible and someone has more knowledge of it, please enlighten me a bit. What engine
size/year do you recommend? He also plans to leave the Allison trans in the truck, so he'd
need to find an engine that will mate to it without any extensive mods. Will the computer need
to be replaced?
Thanks up front...
trinic is offline   Reply With Quote
Old 12-02-2005, 02:49 PM   #2
70rs/ss
Registered User
 
70rs/ss's Avatar
 
Join Date: Dec 2004
Location: Northern AZ
Posts: 7,274
Re: Chevy Engine Swap from 8.1 to ???

He could go to a 6.0 from the Denali sold through some of the dealers like Sciggins Dickey in San Antone for like $3600 (completely new crate motor). Or buy one from a wreck. I wonder if the wiring is the same (might very well be) and then he would only need to change the comp. It may help a bit, on a side note if does decide to do it put me down as the buyer of the 8.1 and it will help him offset the cost of the new motor.

Mike
70rs/ss is offline   Reply With Quote
Old 12-02-2005, 03:31 PM   #3
trinic
Registered User
 
trinic's Avatar
 
Join Date: Aug 2002
Location: Wide awake Wylie (North Texas)
Posts: 322
Re: Chevy Engine Swap from 8.1 to ???

I'll talk to my bro, and see what his plans are now....I'll keep you in touch
if he does decide to go with the swap..

Quote:
Originally Posted by 70rs/ss
He could go to a 6.0 from the Denali sold through some of the dealers like Sciggins Dickey in San Antone for like $3600 (completely new crate motor). Or buy one from a wreck. I wonder if the wiring is the same (might very well be) and then he would only need to change the comp. It may help a bit, on a side note if does decide to do it put me down as the buyer of the 8.1 and it will help him offset the cost of the new motor.

Mike
trinic is offline   Reply With Quote
Old 12-02-2005, 11:00 PM   #4
qksilver
Senior Member
 
Join Date: Dec 2004
Location: Southern Pines NC
Posts: 3,853
Re: Chevy Engine Swap from 8.1 to ???

put me second!
As far as swapping, with that late model of a truck he might do better returning it to stock, if he has the old parts and looking for a desiel. Unless you got a good deal on a complete truck,there are so many small details to make it work. The power acc and computer stuff work together plus exhaust etc.
steve
qksilver is offline   Reply With Quote
Old 01-08-2006, 03:18 AM   #5
Werewolf
Woof?
 
Werewolf's Avatar
 
Join Date: Jun 2005
Location: Raleigh, NC
Posts: 276
Re: Chevy Engine Swap from 8.1 to ???

I know I'm late on the reply to this thread, but I'd tell him to stick with the 8.1. I don't know about the wiring, but I know the 8.1 has a completely different intake and (I think) exhaust. I explored the possibility of sticking one in my 1500 Silverado, 5.3 powered. The 4.8, 5.3, and 6.0 are all pretty much the same, but the 8.1 is different. I don't know that he'd see any mileage difference, anyway. My truck's a 4x4 with a 3" lift and 33" tires and it's only pulling 15mpg on the highway. All he'd be doing is giving up power, IMHO.
Werewolf is offline   Reply With Quote
Old 02-01-2006, 01:24 AM   #6
61burb
Registered User
 
61burb's Avatar
 
Join Date: Sep 2005
Location: crowley, colorado
Posts: 132
Re: Chevy Engine Swap from 8.1 to ???

that 8.1 sure does suck up the gas tho. i have a 04 yukon 3/4 ton 4x4 and i only get 12mpg. that thing will climb a tree if you can get traction.
__________________
61 GMC Suburban
63 GMC 4X4 Suburban
66 Chevy C-10 LWB Fleetside
61burb is offline   Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 01:38 PM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2018, vBulletin Solutions Inc.
Copyright 1997-2013 67-72chevytrucks.com