Here's my situation: When driving in mud, I have a hard time distinguishing wheelspin from normal torque converter slippage(I'm still stopped, but engine rpm's are rising). Normally, the torque converter locks up around 40mph, but I'd really like to have the ability to lock it manually at much lower speeds. Has anyone ever done this before? Or should I just start looking for a 4WD with a 5-speed?

My '86 4Runner went to the bone-yard November 29, 2004 at 10am after roughly 430,000 miles on the original engine and transmission. :-( Looking for something else to wheel in...