team39763

iTrader: (3)

I got a buddy that needs a motor for his 2500HD. He just needs an inexpensive replacement and 5.3L's seem to be popping up left and right for cheaper than a 6.0L. I know everything will swap over, but does the tune need to be changed? Will it atleast run with the stock 6.0L tune? Thanks.

whitegmc2002

iTrader: (3)

if he is not in a hurry hopefully next weekend ill be swapping a 6.0l in my truck and will have a 5.3 for sale with the computer that has a tune in it motor has 99000 miles. he would have to but an harness for his trans to work, bc i would think he has a 4l80e.

nickleahy23

iTrader: (1)

Why would he want to downgrade to a 5.3 in a heavy *** hd? Tell him to sell the truck for a half ton since he must not use it to tow much, or to save up for a 6.0..you can find them for 700-800..check car-part.com

but if he insists on throwing a 5.3 in, you would need to put the flex plate from the 6.0 on the 5.3...that should be all that you need to do and everything else will bolt up..he will use the same harness that is in the truck already so he wont have to **** with his trans..you can even run the 6.0 tune on the 5.3 i believe..worst case just get a blackbear tune or a local live tune on it..

team39763

iTrader: (3)

He wanted a 6.0L, but he really didn't care if you we had to drop in a 5.3 if the 6.0L was available. I don't think he tows much with it. It's just a good looking truck that he cruises in. I found a 6.0L with 130,000 miles on it, but I don't know if he'll go for that. I'll check and see.

pasadenaman

iTrader: (3)

What year 2500? Don't go to 5.3 from a 6.0. Youwill be talked about for years to come on here.

00ChevyScott

iTrader: (10)

I highly doubt he cares

team39763

iTrader: (3)

I don't care if people talk about me.LOL. It's my friend's truck not mine. He was just in a hurry to get his truck back on the road. But I think we found a 6.0L that he can afford and he might have enough left for a cam too.

MustangPunk

iTrader: (1)

To answer your question, yes it will run on a 6.0L tune, prolly pretty rich, and be doggy as hell. I would get a 5.3L tune asap..

budhayes3

iTrader: (19)

What year is the 2500? If it's a 99-00 he will need to buy a crank spacer to bolt up to the 4L80E, as those years had a longer crank and did not use the spacer that the later years do. It will run on the 6.0 tune, but I wouldn't leave it like that permanently, so factor in the price of a tune to the swap.

team39763

iTrader: (3)

I think the truck is a 05, but he says he found a 6.0L for it already. Now I'm trying to see if I can get his old broke 6.0L so I can use it for my next build.