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Old 04-12-2009, 10:54 PM   #1
pokethesmot
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transmission

while driving on the highway it just wont shift into a high gear i have to keep it floored most of the time intill it shifts up higher it use to not do this so whats the problem
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Old 04-12-2009, 11:53 PM   #2
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Re: transmission

huh?
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Old 04-12-2009, 11:57 PM   #3
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Re: transmission

What model transmission? Have you checked obvious things first? Fluid level, TV Cable, disconnected/broken vacuum or electrical lines to the tranny?
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Old 04-13-2009, 07:08 AM   #4
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Re: transmission

fluied level is good as as far as i know everything else is too and i have a 350 tranny
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Old 04-13-2009, 08:05 AM   #5
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Re: transmission

It sounds like you need to adjust your TV-Cable.

http://www.tciauto.com/Products/Inst...ble_adjust.htm

I believe, even though I haven't messed with it in a very long time, you can adjust transmission shifts through your muodulator on the transmission itself, you have to pull the hose off and you'll see a screw there you can turn one way or another. But, I would mess the cable first since it's likely you've messed with that.
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Old 04-13-2009, 09:26 AM   #6
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Re: transmission

While you had the Pan off of the motor is there a chance that you unplugged the vacuum line for the transmission?Wouldn't have to bump it too hard to do that.

Last edited by powerdriver 1958; 04-13-2009 at 09:27 AM.
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Old 04-13-2009, 09:58 AM   #7
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Re: transmission

I just want to make sure im getting this... the truck wont shift into third gear at like 25 mph? could be either a bad vacuum between the trans and manifold or the modulator could be bad too.. You also need to make sure the fluid is red and not smelling burnt
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Old 04-13-2009, 12:03 PM   #8
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Re: transmission

well now im about 90 percent shure its a vacum leak cuz when i push the gas it sounds like a vacuum leak and it was doin it before i changed the rear main seal
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Old 04-13-2009, 09:01 PM   #9
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Re: transmission

Bump
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Old 04-13-2009, 10:40 PM   #10
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Re: transmission

Poke you haven't said anything about checking the vacuum line to the modulator.there is a steel line that runs from the back right of the tranny to a vacuum port behind the carb with rubber hose on each end.That is the 1st thing to check
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Old 04-13-2009, 11:17 PM   #11
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Re: transmission

My tranny did the same thing when the hose on the end of the modulator line cracked and came apart.
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Old 04-14-2009, 12:42 PM   #12
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Re: transmission

well the hose on the modulator looks to be ok but when i press the peddle down i hear a hissing sound like its a vacuum leak and when i press all the way down on the gas i seem to lose speed
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Old 04-14-2009, 08:25 PM   #13
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Re: transmission

well now maybe you have a totally different thing going on,that sounds like the exhaust or catalytic converter might be plugged

Last edited by powerdriver 1958; 04-14-2009 at 09:07 PM.
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Old 04-14-2009, 08:51 PM   #14
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Re: transmission

Quote:
Originally Posted by powerdriver 1958 View Post
well now maybe you have a totally different thing going on,that sounds like the exhaust or catalytic converter plugged
really? it makes a weird sound when i floor it too like a real deep tone that drones on and it dosent even have to be all the way floored to do this
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Old 04-14-2009, 09:03 PM   #15
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Re: transmission

look at the exhaust for bent, Collapsed pipe or a spot that has all the rust gone.Maybe even a spot that the pipe looks looks blue.Have had a couple that backed cars in to a bank of dirt and plugged the pipe up

Last edited by powerdriver 1958; 04-14-2009 at 09:06 PM.
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Old 04-14-2009, 09:15 PM   #16
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Re: transmission

well i dint see any bent pipes or anything i have duel turndowns that dump right after the back axle
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Old 04-14-2009, 09:28 PM   #17
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Re: transmission

can you get someone to try and help locate the source of the noise
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Old 04-14-2009, 09:52 PM   #18
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Re: transmission

well the sucking sound is coming from some wear near the air cleaner
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Old 04-15-2009, 04:00 AM   #19
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Re: transmission

Check the vacuum lines on the intake manifold. It may have come loose and still be hooked up on the trans. Make sure the rubber hoses are in good condition.

You will hear a vacuum from the carburetor especially if the engine is quite.
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Old 04-15-2009, 08:18 AM   #20
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Re: transmission

Get a can of carb cleaner and spray (with the motor running) in the area where you think the leak is at. The motor will tell you where your leak is.
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