My 1999 4.6 sucked a valve and destroyed the engine, the truck was very clean and in my hunt for another motor i came across a 2001 roll over that i bought for 800.00 complete, I removed the cab and then the box and everything is looking great as far as the engine, tranny and rear end so my question today is can i just set my 1999 cab and bed on this 2001 chassis and plug and play.. both trucks are 8th # W The reason i ask is because the 01 only has 80K on it and also the rear breaks are disc and it was real easy to remove the cab which i think i might even do to install the motor in my truck...

 

As far as I know it should bolt up as the major body panels are the same on the 99 as the 01. The wire harness could be an issue and should be checked first. I know 99 had a bunch of changes from the 97-98 models but I think after that most everything was carried over with just a few small changes along the way. Also, check the cluster. The early trucks had a mechanical odometer and Speedo while the later models were electronic.

 

If the vehicle rolled, I would definitely be leery about whether the frame was straight. Same with suspension components being tweaked.

 

It's electronic cluster in the 99 and the frame is in good condition, the truck just has road rash on the sides and roof the bumpers are straight and under carriage is nice, a lot better than mine i have now...

 

originally i was going to change engine but this is so nice it seems like a shame to take it apart!! It has been in storage for 8 yrs this is why low miles it started right up to load on trailer and is all original never been worked on....

 

I really need to know if the wire harness's need to be changed i have both trucks with complete wiring and ecu/pcm... would like to keep the cops with the 99 cab on the 01 everything else...

 

Shouldnt need to change the looms around. If they are bolth the same motor you will be fine. I did the same thing as you only on an 8th gen. Everything swapped right around no questions asked.

 

Thanks a lot lariat, i did take Kingfish's advice and stayed with my frame and swapped complete engine and trans assembly with wire harness from the 2001 to the 99 and when all finished the motor will crank but will not fire up and also the eng service light is on.. Do i need to pull off the harness and install my 99 harness back on to the engine along with the coil packs instead of the cops.. I really hope not, that is a big job!! Should i swap the ECU??

 

If you haven't done so.You need to purge the rail once. First, try starting again, if it's been awhile since the first attempt. It might just fire right up. If not, purge the residual by KOEO's. Key On Engine Off. Yea, don't start, just key to run, let the pump charge the lines, then shut off. Do this 6 or 7 times, then attempt to start.

Also, you can't crank more than 4 seconds continuously. or the rail shuts down.

 

If the CEL is on, read out the codes.

 

When i turn the key on i do not hear the fuel pump run, i would expect to hear it run for a few seconds then shut off but i can not hear it at all also it is my service eng light that is coming on...Thanks for the help!! I did see where someone posted about this kind of a swap and said that i would have to change wire harness and eec along with cluster to keep the pats happy then it went on to say something about setting the wire harness up to waste fire like the old one did, this stuff has really got me confused.... I am all bolted up and ready to go but it only cranks and i do not hear any fuel pump noise what so ever!!!!

 

Check the inertia switch behind the passenger side kick panel. Also check the fuel pump relay and fuse.

 

Everything seems to be good so i am going to recap what i did! I removed the cab from a rolled over 2001 and removed my 1999 cab then i removed the engine and transmission with exhaust and all sensors and wiring left in tack ( it was very simple, only a few motor and transmission nuts and bolts along with the heat shields) and installed it in my 1999 frame and then lowered the cab back down on to the frame and plugged all the 01 harnesses back into my 1999 truck! Every thing matched perfect except for one ground that was in front of engine on 01 and rear of motor on 99 but there was a vacant hole for it on the frame of the 99 so it was nothing, i did grind the surface to make good contact.. Both trucks ran before i started this transplant.... Can anyone tell me if this should work or is there other things i need to do to make them work. I am planning to lift the cab again tomorrow and change back to my original harnesses but do not want to do it unless it is necessary... Thanks in advance and if possible give me some good news tonight ....

 

You are trying to run a 2001 engine intact with a 1999 PCM? I don't think that's gonna work, you are gonna have to switch over to the coil packs and wires. If you try to use the 2001 PCM, then you will have a PATS issue.

 

When did the 4.6L change to COP? I'm not sure and for some reason thought he was using a 5.4L which uses the same ignition system in 99 and 01.