Transmission shifting hard and high

[pizzaworld]

Hey I need guidance concerning my transmission...m1029...it is shifting pretty hard, sometimes jars the whole truck. Is that normal? It revs VERY high before shifting too. Any ideas?




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I am here: http://maps.google.com/maps?ll=36.126638,-86.805799

 

[ralbelt]

Probably vacuum lines cracked and leaking. Replace the rubber lines from the trans modulator to the vac pump.

 

[shannondeese]

I had the same problem. It was the modulator. But I changed the vacuum lines first hoping for the simple fix. Good Luck.

 

[WARWAG]

YUP that was the first thing I fixed. Crawl up undernieth and you will see about a 1 inch 1/4 vaccum hose. This will be on the passenger side of the transmission. Replace that one first. Now jump up to the engine compartment and pull off the entire air cleaner. You will see I believe 3 more on the left side under where the air cleaner was. Replace those. IF you still have a hard time shifting make sure each hose has a good seal. One of the upper metal tubes on my M1028 was stretched from the factory and I had to push the hose down about 3" to get a seal. If you still have High and Hard shifts then its most likely your vaccum modulator. Those are about $75. But the problem will be the leaky dry rotted stretched out hardend leaky Vaccum lines that are leaking and are dry rotted hardened and stretched out and are leaking......... Keep us posted.

 

[pizzaworld]

Hey thank you everyone! I am near lots of autozones oreillys and advances and napas...I've never replaced vacuum lines. Will they have em in stock? Are they just sold by the foot? Again, thank you!


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I am here: http://maps.google.com/maps?ll=36.126671,-86.805852

 

[Stan Leschert]

They sell them by the foot. Cheap! Way cheaper than a tranny shop will ding you for.
Replace any hose that does not flex easily.
You should get out of NAPA for less than $30.oo .

Do one hose at a time, and guard from heat ... exhaust ....
report back when done!

 

[pizzaworld]

Hey everyone you said report back...so it was a super cheap and easy fix... The big and short (probably 3 in) vacuum hose that connects just under the air filter housing close to firewall (is this what's called air cleaner?) was VERY rotted and I cut it off with a knife and replaced it for about $1.50 and now it's shifting clean as can be and smooth...night and day difference.... Thanks everyone for your help!!! I though it'd be an expensive transmission problem but it was so easy. I am very grateful for shared knowledge.

 

[WARWAG]

Thats what we are here for. Something about fixing what you thought was going to set you back some serious Benjarmins but ended up being pennies instead. Thats a great feeling.