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 1973 - 1987 Chevrolet & GMC Squarebody Pickups Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 08-23-2015, 12:01 AM   #1
Skunksmash
Registered User
 
Skunksmash's Avatar
 
Join Date: Sep 2012
Location: TX
Posts: 1,014
5.9 Cummins vs 5.3L?

A buddy of mine is weighing the 5.9 cummins vs the 5.3L (or other LS). Guess if the 6.0 LS was a better choice, we'd go with that instead. He wants to put one of those in a K20. The K20 would be a lifted 4x4, so that might put the cummins ahead of the 5.3. Or would it?

So basically, if you were going to buy a k20 and you had the choice between an LS engine and the 5.9 cummins, which one would you choose? And why? What are all the pros and cons? The cummins is going to be a more expensive swap. But it seems to me that when it comes to adding power, which he's definitely going to want to do, the two engines are pretty much equal.
Skunksmash is offline   Reply With Quote
Old 08-23-2015, 01:07 AM   #2
TwoFiftyShifter
Registered User
 
Join Date: Nov 2008
Location: Gwinnett GA
Posts: 1,803
Re: 5.9 Cummins vs 5.3L?

Big cost difference... Maybe a turbo 5.3L is a good middle ground?
__________________
1982 K10 SWB
1987 V20 - Sold - Doh!
TwoFiftyShifter is offline   Reply With Quote
Old 08-23-2015, 07:08 AM   #3
mongocanfly
Post Whore

 
mongocanfly's Avatar
 
Join Date: May 2015
Location: Alabama
Posts: 14,672
Re: 5.9 Cummins vs 5.3L?

I would go ls...no question about it... I have several buddies with diesels of all 3 big brands and they all have had to have very expensive repairs..they are better when they run but their very expensive to work on and the swap expense would be another thing. You can build big power out of a ls for not a lot of dollars.
mongocanfly is offline   Reply With Quote
Old 08-23-2015, 08:13 PM   #4
86c20
Registered User
 
86c20's Avatar
 
Join Date: Mar 2012
Location: edgartown mass
Posts: 852
Re: 5.9 Cummins vs 5.3L?

i would go 12v or 24v cummins. more the 12 do to is ez of work. it is as simple as a carb 350. if you can read a book and turn a wrench you can fix it. expensive to fix??? that is all relative in the name of power and longevity. now the real ? is who will be doing said work? if you are then its cheap if you are paying then its not. gas and efi can be vary costly as well. ecm harness trans ecm ect...ect...ect. both have good both have bad. if its just a mall show off go gas if its a weekend worrier go gas. if you are going to pull play hard or daily and what a little bit better mpg go diesel. and yes you can get high mpg out of a diesel. there is a guy with a 4b in a burb that gets almost 30 with ac and full of family.
__________________
1986 c20 "the hillbilly" 350 sm465 3.42gears 21mpg at 70mph
1985 k30 "the ice cream truck from hell" no rust az truck
197-8??? c30 "ramp truck" 454
1978 monte carlo 350 350th with 2.73 gears. no rust. sc car
86c20 is offline   Reply With Quote
Old 08-23-2015, 09:02 PM   #5
lilpoindexter
Registered User
 
lilpoindexter's Avatar
 
Join Date: Sep 2010
Location: los angeles
Posts: 1,134
Re: 5.9 Cummins vs 5.3L?

Cummins.
lilpoindexter is offline   Reply With Quote
Old 08-23-2015, 10:27 PM   #6
tucsonjwt
Registered User
 
Join Date: Jul 2007
Location: Tucson, AZ
Posts: 3,189
Re: 5.9 Cummins vs 5.3L?

Diesels are nice, but:

Hard to find good diesel mechanics, and when you do they are expensive.

Diesels have most of what gas engines have, plus expensive extra parts.

Diesels have cold weather start issues.

Diesels historically use more expensive diesel fuel (not now, but will return to being more expensive in the future.)


Having said that, my ideal truck would be a 12V Cummins in a crew cab 4WD.
tucsonjwt is offline   Reply With Quote
Old 08-24-2015, 02:17 AM   #7
andrewmp6
Registered User
 
Join Date: Jan 2009
Location: Louisville,Ky
Posts: 5,811
Re: 5.9 Cummins vs 5.3L?

Cummins will be a little harder to swap and more money to do so.The ls will be a little easier to swap if you buy all the swap parts.Up keep the diesel takes more oil and has to be changed twice a year and the filters are huge and pricey.Then you got the weight balance of the truck if its going off road the ls is a lot lighter.A 12 valve cummins is like 1500lbs vs the 600ish of a iron block ls will be.
andrewmp6 is offline   Reply With Quote
Old 08-24-2015, 02:08 PM   #8
Edahall
Registered User
 
Join Date: May 2011
Location: Goliad, TX
Posts: 672
Re: 5.9 Cummins vs 5.3L?

Depends a lot on the use of the truck. If he is going to be using it for a lot of very heavy towing, then go Cummins. The low rpm torque of the Cummins is nice when towing heavy loads. If he is not interested in shifting a manual transmission, go LS. It costs big bucks to build up a reliable automatic transmission behind a Cummins. As far as fuel economy I get mid 20's with my 3/4 4x4 square Suburban if I keep my speeds down.
Posted via Mobile Device
Edahall 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 09:06 PM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com