Bad vacuum module?

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j_dog00

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Yep 2wd..im going to check bolts again and make sure everything is on..I still haven't gotten the 1 bolt out that is stuck..i wonder if thats causing the TC to not mate properly

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Matt69olds

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If you can’t add fluid, the vent is most likely plugged up with grime. Pouring in fluid displaces the air inside the trans, it would normally exit thru the vent. The vent is on top of the trans, on the passenger side.

5 quarts probably isn’t enough, if you can’t get the vent cleared, maybe jacking up the passenger side of the truck, and slowly pouring in a couple more quarts
 

Frankenchevy

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did you completely empty the trans? when you only drop the pan, only so much comes out.
 

j_dog00

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Frankenchevy all I did was drop the pan..how do you drain it more? But also if its full it should work..even overfull i would think..

Matt69 i will look at the vent and tilt the passenger side up and try that..

Thanks guys!!

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Frankenchevy

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What most people do is called a drain and fill. Drop the pan, replace the filter and put in the same amount of fluid that came out as a starting point. I’m not sure what a standard depth th350 pan holds, but it’s probably around 3.5-5 quarts...tops. How much did you get in?

I’d check your vent tube as recommended. If you’ve overfilled the trans, it’ll want to evacuate the excess fluid out the vent tube or the dipstick.

Then...

Start the truck, shift it back and forth through all the gears. If you aren’t getting any motion without using the throttle, put it in park or neutral with the wheels chocked. With it still running (once it’s warmed up) check the level on the dipstick. If the oil is low, add some if it’ll take it. If it reads normal try putting it into drive again.

Still nothing, then it’s not moving fluid and further inspection will be necessary.
 

j_dog00

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Thanks Frankenchevy I'll be doing those steps tomorrow

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j_dog00

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Oh yes I got in the same amount I dropped

About 5 quarts

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C10MixMaster

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No Drive in any Range

  1. Manual control linkage out of adjustment or manual valve S-link disconnected from lever
  2. Low oil level, blocked oil filter
  3. Low oil pressure, pressure regulator valve stuck, damaged or fell out of valve body
  4. Damaged oil pump drive gear or torque converter hub
  5. Defective torque converter
  6. Forward clutch damaged or not applying
  7. Roller clutch assembly broken or damaged
  8. Broken input shaft


other than linkage and fluid level your probably going to pull it and rebuild it
 

Rusty Nail

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Sad face.

Hay I know a super cool :cool: turbo 350 guy that even drives a squah! @HotRodPC

But srsly. :mad: Y U NO HAZ PIX?

He said there was gonna be pix... :(
 
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Rusty Nail

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This is an easier and shorter post referring to an earlier one. Would a bad vacuum module cause an auto trans to not shift into any gear period? When I pulled it off the back of the trans a little tranny fluid came out, I've ordered a new module just in case. Everything else is good, fluid levels, Torque Converter, flexplate, shift linkage, it's all been checked or replaced. It's just weird that a faulty one would cause a th350 to not shift at all, maybe poor shifting and reduced engine power but not that. I hope it is the issue though it's a cheap fix. Anyone else experience this??

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question #1 = No
question #2 = No
 

j_dog00

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Sorry guys pics coming tomorrow..UPDATE....I got the bolt out! Now all 3 torque converter to Flexplate bolts are in and secure..still not shifting..I haven't pulled the tranny back and i inspected anything yet..interesting side note

When this crap first started, first time i got under..near the TC area..I noticed that two of the big bolts that mate the bellhousing to the back of the block were about halfway out!! After I tightened them it worked! For about a day..then nothing..i dropped the starter and checked the bolts on the other side..they were a little loose so i tightened them..guys i think I'm having a mating problem!! Haha..why would it work after tightening those bolts then nothing??

After every thing..the way its was acting it seemed like it wasn't mated properly..i dunno..just a thought

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Frankenchevy

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The tc may not be fully seated in the trans. When you disconnect all three tc to fp bolts, can the tc slide back towards the trans about 1/8-1/4”? If the gap with it slid back into the trans(separated from the flexplate) is greater than 3/16” you need washers between the tc and fp for a shim. Otherwise, you risk pulling the tc too far away from the trans.

It’s possible to have everything seemingly mated correctly, but the converter isn’t engaging the pump. Which sounds like it’d cause what’s happening.
 

j_dog00

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Im going to take all 3 bolts back out tomorrow..should it be able to slide toward the trans or should it not be able to? To be correctly seated

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Frankenchevy

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I just edited my previous post. Refresh your browser to see what I added.

With the bolts out, it should slide towards the trans ~1/8-3/16” tops.
 

j_dog00

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I'll find out tomorrow..thank you..pics coming i promise!

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