grinding transmission? or what?

[chevyk1500geek]

ok, so my dad owns a 1988 chevy k1500 cheyenne that was purchased in 1987. This truck has an automatic transmission which has two drive gears, highlited and un highlited. SO several years ago, the highlighted one started doing a short high pitched grind at about 15mph, then it would stop(the noise that is). And the other day i was driving it, and in the unhighlited gear, i took off from a stop, and that gear grinded very shortly. When we got home, we switched positions and my dad tested the different gears(P R N (D) D 2 1) and the highlighted drive gear is now acting like a neutral gear! has anyone heard of this or had similar experiences? does anyone know whats going on?

[randy78]

it is a 700r4 if it has two D positions IE it is a 4 speed overdrive automatic

are you sure the grinding is not from the automatic front hubs if they are still on the truck ? they are known for failing and making grinding and such noises

the transmission itself wouldnt make this kind of noise but the transfer case can

synchronizer in it may be worn

it happens

used good cases can be picked up for dirt cheap

esepcially these 208 and 231 ones

very common they are

or it can be fixed for pretty cheap as well


good luck

[chevyk1500geek]

what do u mean by the front auto sensors? Is this a common prblm?