I got a new truck! it's old! (edit. My mobile did something really bizarre to my post, so I am completing it now) I sort of had to talk my wife into this 89 gmc 1500 suburban (k, smallblock, sle package, 4wd autohubs, 3 rows of seats.) Some of the justifications were family trips, my father/son and father/daughter spur of the moment camping trips (and little things like hauling plywood and goats and haybales on a trailer) Trips being a part of this, I need decide on tires. The current tires are survivable for a while, but they are old and showing cracks.... nothing wrong with the tread depth, but they have been sitting for a couple years with almost no use. I do have to deal with gravel roads and "light" off road use- fire and logging road type stuff, not rock crawling or serious mudding. I'd really rather not spend more on the tires than the truck, and I'd like something that won't eat my highway 50 gas mileage..... I expect to replace the "stereo" (yep, i have a stereo mode AM only radio with equalizer!)- put my 2m mobile and possibly a second hf rg in, and i am going to need a 400-800 watt inverter with a usb port retty quick. It looks far easier than the ford stereo upgrade. If anyone has any advice on particular accessory circuits or better/worse locations for addition? I would like to make the gas guzzling beast last- it's a fairly young 130k miles and i can do my maintenance, once I figure out what to do. Assuming that the haynes manual isn't the recommended starting point for the fanatics out there, what is? (Haynes, my lube shop, and the dipstick already disagree on what type of tranny fluid I use!) And is the oil bypass filter modification really worth doing? I've been reading up on it, but I'm having a bit of a "if it was that good, wouldn't it be offered?" disconnect. thanks all.