denalli

i am in the middle of the swap right now but i am facing a problem. the mechanic says that the crank sensor in the lq4 is diffrent than the one in the 07 4.8. he also said that this problem is also in the 06 trucks, is that right? he is suggesting that we do a crank swap from the new 4.8 to the lq4, is that possible? if not what should i do in that situation? i know that i have asked tons of questions but the reason nis that i live in kuwait and i have no professionals in here to ask. i did a search but couldnt get any answer on that. i really appreciate any help.

nighthawk08

don't do a crank swap, you'll end up with a 5.5L instead of a 6.0L.

if the motor your taking out has a 58x reluctor ring, and you want to keep the computer and wiring, just get an LS2 crank. That will bolt into the 6.0 block and give you the right readings. But then you have to worry about the knock sensors.

denalli

so the ls2 crank will fit exactly with no modification or tunning? and what about the knock sensor?

nighthawk08

The ls2 crank will go right in and yeild the same displacement as the stock 6.0 crank.

the knock sensors on the Gen IV's are on the outside of the engine while in your 6.0 they are in the valley of the engine. If you just have to extend wiring, it would be pretty simple, but I dunno if its that easy.

denalli

thanks for the help and for your time. i really appreciate it.

nighthawk08

I forgot to mention, make sure you get a LS2 crank with the 58x reluctor ring on it. If you order new GMPP it will be the correct one, but if you get it used, it has to be a 2006 or later crank. The 2005 would have the same problem as you have now.

ChevyThunder17

iTrader: (45)

You'd be looking at needing a rebalance if you change the crank. The LQ4 piston/rod assembly is a different weight than the LS2 piston/rod assembly, ergo the bob weights are different.

Of course, I could be wrong. But I don't believe I am.

Tootall

iTrader: (79)

He needs to get the rods/pistons balanced together. I don't think that the crank will make a difference, it's the same stroke? I guess check then new crank for ballancing, but I've never heard of that, they're already balanced when they're made?

ChevyThunder17

iTrader: (45)

They balance the crank to the rod/piston combo. Even though the stroke is identical (3.622 inches), the bobweights are different due to the weight difference of flat top LS2 setups versus LQ4 dished setups. He is talking about a different crank using the existing pistons and rods. He needs the crank balanced.

I'm not sure, but he might be able to change out just the reluctor wheel on the crank. But that'll cost money as well.

Tootall

iTrader: (79)

thanks, didn't know that.