I just got a '00 3500 Savana box truck with 150k & no service history. It needs at least 2 exhaust studs replaced and possibly the fuel pump. I plan to take a long trip with it and want to make it as reliable as possible. I'm going to change/flush all fluids and do a tune up. What specific things should I inspect/replace due to time and mileage. Here'* a few I'm thinking of:

Fan clutch, thermostat & water pump.

Belt, rollers and tensioner.

New exhaust manifold bolts and gaskets. I'm wondering if there'* something easy to do to keep the bolts from breaking in the future.

Brakes

Cap, plugs, rotor & wires. Are coils a problem on these?

DRL delete

New fuel tank straps.

Can't find an edit button.

* change all filters

That'* a good starting list...
If you are doing fuel tank straps, drop the tank and change the fuel pump out. Not knowing the history, this is a BIG to-do thing.

Any signs of coolant around the intake manifold? Might as well do those to.

Any signs of hard starting? (not cranking) Take a peek inside your intake plenum and see if you still have the older style poppet injectors. Upgrade them to the new injectors.

Other than that, the 5.7 is a good engine all around. Keep the oil and coolant in, and it will last forever.

Yes, EDIT is turned off for multiple reasons. If there is a correction that needs to be noted, just make another post exactly how you did. We prefer it that way.

Thanks for the tips. I guess I'll pull the intake off while dealing with the exhaust bolts. I've only run it on starting fluid, which it fires up on instantly.

I forgot to add U joints to my list.

The truck has a wooden plank floor, so I'm just going to cut out an access hole to get to the pump. I'm not sure if I'll actually replace the tank straps. The truck has some rust, but nothing horrible, besides the rockers under the doors. I might add a safety brace under the tank just in case and have the tank straps on hand.

The truck hadn't been run for a few years, so I want to run a fuel system clean thru it. Is Techron OK with GM stuff?

What'* a recommended oil flush? I usually take off valve covers and oil pans and use spray carb cleaner, then do a few oil changes real quick with cheap oil, then run full synthetic. I don't think the oil pan can be dropped on this because of the cross member.

If the fuel is years old, you won't be able to make it usable. Once you get the sending unit out, siphon out all that old fuel and put in new fuel, replace the fuel filter.

You can flush the oil in a few ways. Dump a can of seafoam in, run the snot out of it for awhile, then change the oil. Or extreme would be to fill the entire engine with kerosene, let it sit for a couple days, then drain it. Put cheap new oil in it, run it, change it, cheap oil again, run it, change it then put new good oil in. Its all what your wallet afford. +

So it has never warmed up of moved or shifted gears.

I would do everything that was discussed above in the following order:

1. Diagnose likely bad fuel pump by checking fuel pressure with a gauge when the ignition is on, if low then replace fuel pump.
2. Start it, let it warm up, drive is around a couple of miles, does everything work without bad noises? If "yes" then proceed to Step 3. If "no" then fix whatever is broken next then go to step 2.
3. Do most of that stuff above. Don't forget tires based on build date not eyeballing the sidewall for cracks.

Personally, I wouldn't worry so much about cleaning the engine out. Maybe do an oil/filter change with some non-special 10W30 and drive it a hundred miles then change oil and filter again with some good full synthetic. Sometimes running cleaners etc. through causes more than it solves. Unless there are bad noises that sound like unclogging might help, then yeah add some sea foam to a crankcase of clean cheap oil and let it run for a while, then change oil and filter to another batch of cheap oil, drive it 20 miles, change oil/filter to the good stuff.

My $0.02 .

Oh yeah: Differential drain and fill.

I ended up getting a Rockauto fuel pump/sending up and temporary installing it. The truck started up fine ( I cycled the key a few times to clear the lines before starting it ) and ran ok, which is surprising due to the old gas. The pump install is temporary because the old lock ring was too bad to reuse and I'm still waiting for the replacement one. The big issue is the o ring.

How do you guys get the sending unit in the tank? I tried both the new black o ring and the original GM orange one. I didn't have anything to lube the o ring. What'* the best method, o ring on the sending unit or on the tank? I did check that the replacement sending unit is the same size as the original GM unit.

Are you sure you got the correct sending unit? Rockauto has a tendency to ship incorrect parts. This happened to me a couple months ago. It even boils downt to the locating lug on the sending unit.

It looks exactly the same, but I didn't mic the dia of the top part where the seal sits. I did have to pry the OEM unit out of the tank. I'm going to try to install the old one back in, just to see if does the same thing. If so, it might be from rust on the rim of the tank opening. Hopefully some silicon grease will help.

Now that it'* running, I'm going to look into the broken exhaust bolts and probably pull the intake off. I do notice a tiny oil leak at the back next to the distributior. Any tips for that. I'm especially interested in what causes the exhaust manifold bolts to break.

Defects, fast heat cycles, poor repairs, impacts, etc.