Swapping parts from my old truck to the current one...

One of the items is the 3.73 posi rear, then the engine and transmission. (LQ4/4L80E)

My truck is a 2WD RCSB. I tow a 1500lb open trailer with vehicles ranging between 3300-4200 lbs several times a year. The 4L80E is stock with approx 50K miles on it. The engine is an 04' LQ4 with approx. 60K miles. It has a TPiS ZL10 cam, 1.75" LTs with cats. The exhaust is dual 2.5" into a Magnaflow muffler with a single 3.5" exit. Also has efans and a ported TB. I have 31" tall tires, from what I am seeing - the 4L80E is meant to tow in OD.

Given the weight I tow, size of the truck, and figure between 50-60 mph speeds... what ratio will be better for me? I am wondering if it is worth seeing that I tow with the truck only about 6-8 times per year. Mostly I daily drive it and use it to haul parts for projects.

I found a great deal on a set of 4.11s, and with the rear out of the donor truck - now would be the time to do it vs. laying under the truck at a later date. I just need to make sure that the gear set is compatible with the abs, etc. I've come to realize that not all aftermarket gear sets are created equal.

 

when towing with a gas motor anytime you can run gear run it....i have 35s and i run 488s

 

Did more investigation, the gear set wasn't compatible with abs for some reason. I have my stock rear out of my old truck sold for a good price. I am now looking at buying a complete kit: posi, gears, etc. I am tossing around 4.10/4.11, 4.30, or 4.56 ratios. I just need to decide what I want.

 

I miss the factory 4.10 rear in my old Silverado and that was bone stock. I wish I wouldve swapped to 4.10s in my truck now but I went with the "if ain't broke don't fix it" route.

 

thats a first for me to hear that

 

2010 Silverado 2WD Auto 4.3 to 6.0 swap. What would be the differences in doing this year swap? I just picked up the truck and it needs a transmission so I got it fairly cheap and want to do the 6.0 swap. Thanks for any help you could give me. I have a complete LY6 engine from a 2008 express van and was wondering if I could use this engine?

 

In middle of this swap. Are the mounting brackets off a 2500hd the same as the 1500? They look like they will work and from what I can tell both have the same part number on actual mounts. Thanks in advance. Both 2006s

 

Engine mounts are the same.... so yes it will work

 

Thanks to 03Sierra for all the help.
Pigtail installed on White and Tan wires, ready to re-Pin PCM.
Appreciate the research, excellent pictorial description.
Most helpful.

 

pretty sure you don't need to rewire the PCM for a simple gear swap