Official NBS 4.3v6 to GEN 3 V8 swap Guide

Guys i need some help. I just did my swap based off of this thread, but im having motor mount/frame mount issues. I have a 2006 single cab silverado 4x4 with the 4.3 and a manual 5 speed. I bought a 2003 5.3 engine. The motor is in my truck, mated to the transmission and i have the bolts in the passenger side frame mount. But my drivers side is not lining up. I used the v8 frame mount on the passenger side, and had to use my v6 motor mount on the drivers side for 2 reasons. 1, the v8 mount i have is made to mount flat, and my frame has the tubes on an angle, and 2; my tubes are longer then the v8 frame mount on the drivers side. So couldnt mount it even if i wanted to. This is a picture of what i have on the drivers side with the passenger side bolted up:

Attachment 9243
Attachment 9244

you sure you got 1/2 ton 4x4 mounting plates & mounts? mine bolted right up.

I got the correct motor mounts. Not sure I have 4x4 frame mounts though. Are they different in a 4x4?

yeah, 2wd & 4wd frame mounts are different
can't find the part numbers off-hand, but if you ask the dealership for the frame mounts for a 4x4 1/2ton, they should be able to get you the part numbers. usually eGay, the classified section here, or parts yards are the best places to find them cheap

Quote:

---

Originally Posted by zebra

yeah, 2wd & 4wd frame mounts are different
can't find the part numbers off-hand, but if you ask the dealership for the frame mounts for a 4x4 1/2ton, they should be able to get you the part numbers. usually eGay, the classified section here, or parts yards are the best places to find them cheap

---

Good deal, thanks for the info man. Ill see what i can find. Another question, the motor i bought was missing the evap solenoid (one right behind the throttle body). I went and bought a new one at autzone but im still missing the line or hose that connects to the top of it. Where does that go? i may have to just buy a hose and run it myself but i dont know where the other end of the hose/line goes. Also, for some unknown reason the return line for the fuel, is gone, along with the clip and bolt that holds both the main fuel line, and the return line down. Is that something i can get from a dealer?

the evap solenoid has a flex line that runs back to where the fuel lines are
http://www.ls1truck.com/upload/files...es%20after.JPG

should be able to find one from a junk yard a lot cheaper than a new one (so long as the yard didn't cut it)

as for the fuel lines, i can't remember if some of the late model trucks went to a returnless system or not

Quote:

---

Originally Posted by Selbyvince

Good deal, thanks for the info man. Ill see what i can find. Another question, the motor i bought was missing the evap solenoid (one right behind the throttle body). I went and bought a new one at autzone but im still missing the line or hose that connects to the top of it. Where does that go? i may have to just buy a hose and run it myself but i dont know where the other end of the hose/line goes. Also, for some unknown reason the return line for the fuel, is gone, along with the clip and bolt that holds both the main fuel line, and the return line down. Is that something i can get from a dealer?

---

you have a returnless fuel truck. 1 supply line and 1 evap. unless you already have you need a returnless fuel rail. tell your tuner to eliminate emissions and change fuel reference accordingly.

alright im confused then. I have two hard lines coming up from the fuel pump. And i do have a return style fuel rail on this 5.3. Both of the hard lines on the truck are the same size as well.

How am i suppose to plumb this up? I have to get a returnless fuel rail to plumb up one of the hard lines, and the other hard line goes to the evap valve?

Also i already have my ecu from nelson. They tuned if for a 2006 5.3 according to the sticker they have on the back of it. I never said anything about if i was returnless or return style to them, does that say anything to you as far as how they tuned it? Or should i give them a call on monday and try and find out.

Thanks for all the help guys, id never get this figured out without your help. Also i ordered a new set of 4wd 1/2 ton motor mounts yesterday off of ebay.
Part number: Left side: 15113849
Part number: Right side: 15113847 Anyone know if that is the correct part numbers for what i need? there wasnt a picture so not sure what they look like, but according to gm that is the motor mounts for a 2003-2006 4x4 1/2 ton silverado with a 5.3.

Edit: I had them remove the egr/air injection as at that time i didnt know if i had it, but my headers had the port. Im not sure if they deleted the evap or not though in the tune as i didnt mention anything on that. BUT, i do live where we have to do emission testing. With no cats going back on, and lets say i hook up the evap valve like im suppose to (considering its not turned off in the tune). Will i still pass emissions? they dont really do a visual inspection, just hook up to your obd2 port and read. I know i will have at least one "not ready" status for the cats. This motor didnt have air injection, but its supposibly turned off in the tune (not sure if that will give a not ready status too even though i didnt have it).. Just trying to be prepared on if i will pass or not.

Ok, i have 2 sets of the return style fuel rails. And cant find not one set of the returnless rails. Does anyone have a set laying around??

just buy it. sell both sets of return style to recoup.