2002 Express Cargo Van, 3500 LWB 8.1L, Low miles

[a990dna]

Hello,

I need some general advice. I ordered my G30 Van in 2002 and was originally a company fleet vehicle. As indicated in the title, it has the 8.1L Vortech... I loaded it with full power, 3.73 posi, HD trailering package - essentially the works. When new, I also had it upfitted at Commercial Van Interiors.. it wasn't used much, when I bought it from the company in October 2009, it only had 10K miles. This was all city street driving with minimal loads, no towing.

My question is what oil should I use to extend the life of my new Chevy Express with a Big Block? It uses oil, about 1 quart every 1000 miles... I guess it's normal for this 496ci engine.

The company had the oil changed in regular intervals.. they used 5W-30 Pennzoil dino. I recently changed to Mobil 1 5W-30 Synthetic.. It appeared to clatter more at start-up, when cold, at idle, with the Mobil 1 oil and filter. Therefore, I removed the Mobil 1 oil and filter and went back to the Pennszoil 10W-30 dino and Purolator oil filter to play it safe. One tech recommended I run a bottle of GM EOS and drive it for good break-in period on the freeway.

Ultimately I want to use it for towing... it has a heavy duty class 5 hitch.. engine never runs over 180 degree coolant temps.

Any insight on the 8.1L will be grealty appreciated...

Thank you

 

[addyguy]

I've read Chevy Big-Blocks love thier oil, and a lot of it.

Some consumption will be normal, but with how low the miles are on yours, I'd guess your rings are gummed up.

Change the oil, add a quart of MMO to the oil fill, and run it 3k miles. While doing this, give the van several 'Italian Tune Ups' - run it good hard to try and free stuff up.

Another thing to try while doing this MMO run is to do a 'piston soak' - pur MMO down the spark plug holes, let sit overnight, crank the MMO out, put the plugs back in, and again, run the wee out of it a good few times.

All these things should 'free up' the rings, and help consumption go down.

 

[mfd111]

GM had a TSB on these engines. I do not remember the TSB number, but it had to do with installing new intake gaskets and longer or different bolts. This would in most cases cure the oil consumption or at least slow it down. We had some 8.1's in our fleet that did the same thing. Go to a good GM dealer and ask. If they say that they never heard of it, try other dealers.