LOST 2nd GEAR?

[screamer]

Hi everyone. I need some advice. I'm not sure but,I think I lost 2nd gear in my Th350. My Blazer rev's to about 25 mph (no tach) then shifts. No shift before that or after, even at highway speeds. Could it be the vaccum modulator or maybe the vaccum line? I'd hate to take it to a shop and have the guy tell me I need a rebuild when I really don't. Thanks in advance.

 

[kevin400ex]

what if you try and manually shift it?

 

[adamforsythe]

what if you try and manually shift it?

I second that

 

[screamer]

I tried that. Started in 1st then shifted to 2nd. But the transmission didn't shift. I put it in drive and it would shift....at about 25mph. I don't know much about transmissions. Anybody got any ideas?

 

[Chevy911]

Just a quick guess, but it sounds similar to what happened when my vacuum line came loose for the modulator, the truck shifted at the same RPM as if it was at full throttle even if you were just barely on the gas. It would take forever to get it to shift unless you floored it, but it would eventually shift. I also lost all compression braking as well, does your truck seem to coast when you let off the gas then grab or slam very hard when you apply the gas again? if so, it could be as simple as a loose or cracked vacuum line.

 

[Chaddy]

Hi everyone. I need some advice. I'm not sure but,I think I lost 2nd gear in my Th350. My Blazer rev's to about 25 mph (no tach) then shifts. No shift before that or after, even at highway speeds. Could it be the vaccum modulator or maybe the vaccum line? I'd hate to take it to a shop and have the guy tell me I need a rebuild when I really don't. Thanks in advance.

Time for a rebuild

 

[Cowboy_80]

th350 rebuild is easy. big screw driver, a hammer, and some pliers are the main tools you'll need on the insides. Get a manual to do it, but don't worry, it is easy to accomplish.

 

[screamer]

I can't even see the modulator. And I can't reach it either. It seems to be tucked up behind a brace/ mount. I can follow the vaccum line but then I reach a point where I can't go any further cause my hand won't fit. Is there a trick to this? I have a 203 transfer case if that helps any. Do I have to cut a hole in the floor?