What I've done in the past is drain the factory oil at 1K, fill with dino and drain that at 1500 miles (500 miles on the second fill)- thinking being that the two drains will flush the crud from the block. Then I fill with synthetic. With this particular Tundra I just changed over at 1K and in the process I noticed a little slop in the manufacturing process. When I changed the lube in the transfer and differential housings I found serious chunks of metal from the factory guys cutting the plug hole threads. Hard to believe they can't take 10 seconds and wipe the crud out - I took the shavings to the dealership and the foreman blew it off as typical. I might have blasted the oil foam/cotton air filter too soon as I've since corresponded with a couple more well educated guys in the field of petroleum engineering. I've got a couple more takes on the numbers - as they said, ask 10 engineers and you'll probably get several different answers - anyway - they all favored paper air filters and all stated that as the paper filter gets dirtier it also becomes more efficient at filtering out dirt!! but it also restricts air flow more. Only one thought my high silicon count was due to the Amsoil air filter. The others attributed it to crud left in the engine from the manufacturing process, the engine break-in process, possible contamination from the collection process (crud slowly leaching out of the drain hole). Based on the axle housing crud this is a possibility! This assumption was based on the numbers from the Chromium wear - Zero (0), which is a direct read as to ring wear. I've also got 15,000 miles on this oil with one filter change at 10,000 miles. I'm running Amsoil 2000 0-30wt. (I've also got the dual remote oil filtration unit installed with SDF15 and BE100 filters) They said the contaminants will accumulate as will the wear metals using extended drain intervals, which isn't a problem to the engine using a high quality oil filter but the numbers will be higher overall than if I drained at recommended intervals. The Tundra has an oil cooler which I'm sure has a copper core. So prior to the core becoming oxidized, copper will show up in the analysis. They all recommended another analysis at 5,000 miles and then another in February 2003 to determine a pattern (baseline?) which will then give me a basis to make an educated opinion on what's going on within my engine and if there appears to be a problem they can probably pinpoint the reason. They expressed confidence that my numbers will be within the normal to below normal range with my current oil filter setup after another 5K as I just drained my oil (all 8.5 quarts). We will see. IÆll stay with the Amsoil air filter for another 5K. Anyway - The mods to my Tonka: I've installed the ARB rear locker. I've got a pair of raceway coilovers for the front setting in my garage as I'm waiting for my rear spring set (lifted 2.5 inches and rated for 1K#Æs of bed weight) from National Springs to get here - maybe by the middle of March hopefully. Sway-A-Way is coming out with rear shocks next month for a two-inch rear lift and I'll install them to complement the coilovers and rear leafs. I've got the ARB bawl calf front bumper on order - should be here in April I'm hoping. I'll put a winch on that bumper and I should be good to go this spring when I get on a few back trails that lead to some good fishing lakes. The only people on these lakes are fly-in dudes and damn fool hearty 4wheelers. IÆve also got the front skid plate from Skid Row and will get the rest of the skid plates from Eric as he develops them. Their top notch and reasonable. When these tires wear out and if I feel the need for a little more ground clearance I'll go with 33's and re-gear to either 470 or 488 - To my knowledge no one makes the 470 for the Tundra so I'd have to get them off a Taco as it now stands. Sorry about the long winded reply but since I may have jumped the gun on criticizing the air filters I couldnÆt figure a way to shorten this.