It's really easy to keep it clean. The first cleaning is the toughest. After that, some minor cleaning every time I wash the car. Spray it down with some degreaser, rinse, wipe down with rag then give a light dusting with Armor-All tire foam.
The reason why my trans looks so clean is because it's new, less than 1,000 miles on it, but my old trans didn't look too bad itself.
And yes, my coolant bottle looks absolutely horrible.
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Bobby
Died 5/1/08, resurrected 5/15/08
ASCD SD hood, 17" Bullitts, Overkill PCM, 3.4" Pulley, NGK TR55IX, K&N 9" cone filter, JimmyC D/P, U-bend removed, Flowmaster 40 series, Hooker big bore tips with resonators, S/B brake lines, drilled/slot rotors, GMPP handling kit, KYB struts, F&R strut supports, HID's, LED's, 2.5" Air Dam, red GTP overlays on custom badges, white rear insert.