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need some guidance

tyler2k

Full Member
Joined
Aug 16, 2015
Messages
18
so I have a 04 avalanche that's coming up on 295k with the original motor and trans.  the motor is burning oil and coolant so iv been trying to figure out a path to take.  I'm getting my trans rebuilt while I fix the body and I was tossing around the idea of putting a 6.0 in it,  but after reading most people are saying if your not planning on modding it then the swap is a waste and just do stuff to the 5.3. this truck is my dd, it rarely tows because iv got 2 powerstrokes, so my issue is do I drop in the 6.0, issue there is im obviously gonna buy a used one SSL that means I don't know what im getting, if I build the 5.3 obviously I'm gonna need heads and while there I'd do all new bearings and probably pistons and maybe a mild cam and headers because the truck definitely needs a bit more power.  so what would you guys do
 
When I was in your shoes I bought a 460 hp 6.0 crate long block.  Everything needed to complete the motor came off of the 5.3, although since I was running a supercharger on the 5.3 I was already using larger injectors than stock.  To support 460 hp would probably need bigger than stock 5.3 injectors although the stock flex-fuel motors do have larger injectors than the non flex-fuel motors which may be big enough.  I do my own tuning so tuning wasn't an issue for me.
 
while that would be fun im not trying to go crazy Haha.  I just want a bit more power cause it dies pretty hard on hills with the bigger tires. just looking for cost effective and reliable
 
For some the coast for a rebuild is more (machine work) than a new crate engine.
You also mentioned new heads.

There are a slew of crates out there. Summit Jegs are just a couple. There is member on
here that went with a 6.2 from Summit. As far as the used 6lt. You can still find low millers out there.
If you can find a local yard most carry a warranty. The thing I would be causes about is the cam and intake. Remember
you have a 6k+ truck to get started and you tow. Keep it in the power band that you will be using.

There is also a GM reman. crate 5.3 and you could go with 410's.
 
I'm planning on doing the rebuilding myself,  I'v seen 6.0 for like 1200 with in the 100k area around me. I'v seen 5.3 heads for about 500, so I'm thinking I could rebuild the 5.3 for around 2k and have basically a brand new motor,  but I'd like to have a bit more power.  so im at a loss as to which way to go
 
have your 5.3 block bored out a little when you rebuild it

5.3l = 325cir = Bore 3.779" x Stroke 3.622"
6l = 364cir = 4.000" x 3.622"

I am guessing that is what GM did I cannot beleive they would design a new block so soon inlife of the original 5.3l

I am not sure what block can handle but little research and you got ya a cheap motor.
 
About the most you can get out of the 5.3 blocks is 5.7 liters displacement.
 
tyler2k said:
I'm planning on doing the rebuilding myself,  I'v seen 6.0 for like 1200 with in the 100k area around me. I'v seen 5.3 heads for about 500, so I'm thinking I could rebuild the 5.3 for around 2k and have basically a brand new motor,  but I'd like to have a bit more power.  so im at a loss as to which way to go
You will never be able to rebuild a 5.3 completely for $2000 unless you have your own machine shop.  Also remember that you get a warranty on a crate engine (rebuilt long blocks are about 6K).  But a good used 5.3 is probably the most practical thing to do, given the miles on the vehicle.
 
I rebuilt my Corvette's LS1 for about $2400, including $900 to the machine shop for honing the cylinders and decking the heads and block.

I purchased my Avalanche's 6.0 long block for about $3600 with a 2 year warranty.  Warranty paid off when engine dropped a valve after 4 months and 4000 miles.
 
tyler2k said:
I'm planning on doing the rebuilding myself,  I'v seen 6.0 for like 1200 with in the 100k area around me. I'v seen 5.3 heads for about 500, so I'm thinking I could rebuild the 5.3 for around 2k and have basically a brand new motor,  but I'd like to have a bit more power.  so im at a loss as to which way to go

No Replacement For Displacement. Torque is your best friend. If your stuck on the 5.3 "410's". Just me I would be looking at getting as close to 400' lbs. as budget would allow me.
 
I'm not stuck on the 5.3, I'm just looking at what a used 6.0 goes for by me.  I'd prefer the 6.0 for the extra power and torque but if it's close in price I could have a basically brand new 5.3 rather then a 6.0 with a 150k on it and I don't know the history of
 
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