Hard time deciding on vehicle upgrades during engine swap.

[bobfoe95]

Vehicle is a 2004 Chevy Silverado 1500. I am looking to build it into a general overland/travel vehicle. The truck had the beloved castech heads, which of course cracked. Dexcool has been mixing in the combustion chamber for 30k miles and the motor is so full of sludge a swap is in order.
I have decided to swap my existing LM7 5.3 with a LQ4 6.0. I am currently gathering and researching for the swap.
I have been very back and forth about what direction to go. Of course these engines have a seemingly unlimited supply of upgrades, but at what point does reliability start to decrease?
I have had lists for aluminum radiator upgrades, electric fans, new intakes, headers, and so on. The more I think about it the more I think that the stock engine components are more likely than not perfectly suitable. Why spend the money on what could end up being more headaches and reliability issues over the road?
At this point I plan to replace all components with factory original and upgrade only the trans cooler and power steering cooler.
I am looking for opinions on what to do. I plan to upgrade the truck to coil overs and run a 33 inch tire on stock ride height.

 

[Halligan]

Stock works just fine. Spend the money on suspension upgrades or gear storage.

 

[rayra]

seconded. The vortec motors are very good just as they are, and you'll have an easier time of making repairs far from home, the more stock it stays.

I would definitely recommend changing the plastic heater hose connectors at the firewall up under the cowl (over the #8 coil).
As for the Castech thing the factory fix is a $6 Delco stop leak bubble pack and it has worked perfectly fine on my Suburban.

The only other thing I can think of offhand in that year range is the design change of an integral baffle in the driver side valve cover instead of an external EGR valve. Gets to be a problem on high mileage engines when the drain holes in the baffle clog up and you start aspirating a good bit more oil, which will pool in the central chamber of the intake manifold and eventually cause a huge smokescreen to be laid, seemingly indicating a far worse engine problem. It's a $20 fix.

That sort of info and a bunch more of the typical GMT800 issues are in the Expo topic link in my sig.

And a bunch on upgrading the trans cooler both there and in my own build topic.

And one last thing, if you are swapping to the 6.0 already I'd also suggest going to the 4L80E or at least a 4L65E 'upgrade' of your 4L60E. The death knell for 4L60Es seems to come when they are held at a high RPM and heat range as with towing on a long grade. Get them up around 275F and bad things happen with differential heating in the steel and aluminum pump parts. And with these vehicles typically coming with 195F thermostats, typical summer operating temps do not leave very much margin for error in the loaded trans temp. It's depressingly easy to exceed.
Unfortunately, the typical GM in-tank trans 'cooler' loop is actually designed to be a heater, to get the trans up to operating temp in cold climes. Get out in the sunny hot desert and it's a real hazard.
One immediate remedy is that you can get away with a cooler thermostat without failing emissions or making any noticeable impact on performance. Stick a 180F or even 160F in there. I'm running a 160F and it's made a big difference in operating temps. Coupled with the huge trans cooler and its change of placement I get significantly cooler operating temps in both engine and trans. Rarely exceeding more than 40deg over ambient in the trans. And about 165F engine temp. And that's with the trans loop still passing thru the radiator tank before going on to the new trans cooler.

 

[bobfoe95]

Thank you for the reply’s. Funny enough, I have already had most of the problems you mentioned above! Great idea on the cooler thermostat to help with the engine and transmission. What is a good remedy for the plastic clips? I’ve had those fail many times and usually just clamp the hose to the left over stub. I will look over your topics. Thanks again!

 

[85_Ranger4x4]

When I V8 swapped my Ranger someone recommended running a 160* thermostat... heat in the winter was lukewarm at best. Basically in Iowa it was a joke. I run a oem spec 190* now and it seems to work fine for me plus the heater works a whole lot better.

 

[javajoe79]

Definitely stay with stock parts unless an upgrade is needed.

 

[rayra]

Thank you for the reply’s. Funny enough, I have already had most of the problems you mentioned above! Great idea on the cooler thermostat to help with the engine and transmission. What is a good remedy for the plastic clips? I’ve had those fail many times and usually just clamp the hose to the left over stub. I will look over your topics. Thanks again!

You can readily just clamp the heater hoses right on the firewall stubs. With a pickup / no rear AC/heat, the stab-on fitting's only purpose is ease of assembly on the line.
The only real issue is making the new connections while they are easy to get to.