L31 vs L33 Differences? - S-10 Forum
S-10 Forum is the resource on GM S-series trucks, Suspension, engine information, Body Modifications, painting tutorials.  Modifications to suit every need, budget and whim

L31 vs L33 Differences?

Go Back   S-10 Forum > Engine and Drivetrain Tech > V8 Discussion
New User? Register Forgot Password

LinkBack Thread Tools
Old 03-08-2012, 04:36 PM   #1
Registered User
Exphius's Avatar
Age: 28
Join Date: Jan 2012
Posts: 283
Location: middle of nowhere
User is: OffLine
L31 vs L33 Differences?

Hey guys, im getting ever closer to starting my v8 swap in my sonoma and spent ALOT of time doing as much research on this project as i can. I'm feeling pretty confident now on this project however there was one small thing i can seemed to find anywhere online. The differences between the 5.3 and the 5.7 besides the obvious. The differences im wanting to know about is the mounting of an L33 instead of an L31. Would AA adaptors and energy mounts work just the same on the 5.3 (L33) as they would for the 5.7 vortec

If indeed these mounts will work on the 5.3, my next question would be would an oil pan need to be custom made for it?
This forum thread says you wont need a custom oil pan made with a 2" body lift with the 5.7, would same apply for the 5.3? or is the design different.

FYI first time engine swap for me so please dont be to hard on me ><
Sponsored Links
Old 03-08-2012, 09:41 PM   #2
Registered User
Join Date: Feb 2012
Posts: 120
User is: OffLine
Re: L31 vs L33 Differences?

L31 is old style block like all the other 350 cubic inch motors are. The L33 is a new style ls series block completely different in all aspects. You can't use 4.3L mounts on either swap. You have to buy v8 swap mounts and the bottom mounts have to be 2.8L not 4.3L. If your vehicle has a 4.3 you will have to remove those mounts and put 2.8 mounts on it. Both swaps have been done many of times and there should be way more then enough info online and on these forums explaining what should be needed.

I am not understanding how you are not finding any information on it. Makes no sense to me.
Old 03-09-2012, 12:21 AM   #3
Registered User
Exphius's Avatar
Age: 28
Join Date: Jan 2012
Posts: 283
Location: middle of nowhere
User is: OffLine
Re: L31 vs L33 Differences?

I apologies, ill clearify a little better. I had forgot a link to add as to what i am talking about. My top 2 links on my original post are for conversion adaptors and mounts that work for the 5.7 vortec. this information was gathered here.
However i am going to be using an L33 motor instead and was wondering if those same conversion motor mounts would work. They supposedly bolt right up to the 4.3 mounts and the v8. The 2 links in reference to the mounts do not specify what v8's that they are limited to. I am guessing the mounts will bolt up to my existing mounts and to the L33, but would this present a problem in engine to bell housing alignment/spacing?

Oh and im finding all kinds of info on it. im pretty sure ive seen most of it all. Zr2usa/s-10 forums/ls1tech have been huge helps. I pretty much have a good understanding what this project is going to require.
To give you an idea of what im doing. im putting a L33 from a 06 silverado into my 01 sonoma zr2. Im in the stage now where im starting to aquire everything before i start the conversion. I picked up the motor and getting ready to look into current performance wiring for a wiring harness. If the "conversion" mounts do work for the 5.3 with no issues then ill be getting those next, followed by a set of 4wd patriot headers, etc. My plan is to collect everything i need and follow up with a bit more information research and start this project come mid May. I plan on spending around $1500ish on everything and doing all the labor myself and a few mechanically inclined friends over the summer (if it takes that long). Im so-so mechanically inclined but never done anything this elaborate before so this is all new territory for me. I guess the only way to truely learn is to do it yourself.

Hopefully you understand what im talking about now and hoping you have an answer. If you have any other suggestions, tips, or any useful information let me know.
Sponsored Links

Quick Reply

Register Now

In order to be able to post messages on the S-10 Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.
Confirm Password:
Email Address
Please enter a valid email address.
Email Address:
How did you hear about us?
Enter a URL or Site name of who refered you to this site. (required. Only admins can see this)
Please enter your two letter state name to help other users and clubs find local users to them.(required)
Please select your insurance company (Optional)
Date of Birth
Your date of birth and age are displayed in several places on the forum. Only the administrator will have access to your date of birth should you choose to hide it via the privacy option below.
Month Day Year


Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.

Thread Tools

Posting Rules
You may post new threads
You may 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
Trackbacks are On
Pingbacks are On
Refbacks are On

All times are GMT -4. The time now is 05:43 PM.

Powered by vBulletin® Copyright ©2000 - 2011, Jelsoft Enterprises Ltd. SEO by vBSEO 3.2.0
vBulletin Copyright ©2000 - 2016, Jelsoft Enterprises Ltd.