Author Topic: TH350 Problems  (Read 1443 times)

Offline uprising

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Re: TH350 Problems
« Reply #15 on: November 22, 2019, 09:34:47 AM »
Ok, i will order a filter and gasket again. Also a new modulator and maybe a new sealkit for the transmission (if the seal between engine and transmission is damaged)
Which nut sizes do i need for the transmission remove? I only have metric nuts...

Online Shifty

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Re: TH350 Problems
« Reply #16 on: November 22, 2019, 09:37:43 AM »
Might as well invest in a set of SAE sockets and wrenches if you intend to do a lot of work to your elderly Chevy.   ;)
87 V20 Standard Cab Longbed (current)

87 R30 3+3 Longbed (days of yore)

Offline uprising

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Re: TH350 Problems
« Reply #17 on: November 23, 2019, 12:46:01 PM »
 :) ;)
I will. Till now i try to do it with metric tools but it doesnt fits well. :)

Will give a feedback after i changed the filter, gasket and Modulator!

Offline uprising

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Re: TH350 Problems
« Reply #18 on: November 24, 2019, 01:51:58 AM »
Short question:
My wheels have 6 lugnuts! So, no c10 or c20 :-\
What can it be?

Online Shifty

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Re: TH350 Problems
« Reply #19 on: November 25, 2019, 08:47:30 AM »
PM sent.
87 V20 Standard Cab Longbed (current)

87 R30 3+3 Longbed (days of yore)

Offline Irish_Alley

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Re: TH350 Problems
« Reply #20 on: November 26, 2019, 09:55:51 PM »
the 6 lugs denotes its a k15/10. it can have 8 lugs and be a C/K20 or C/K30. generally the more lugs the higher the gvwr can be. theres other factors that come into play with gvwr but axles are one of them
If you cant tell yourself the truth, who can you tell it to?~Irish_Alley

When you have eliminated the impossible, whatever remains, however improbable, must be the truth ~Sherlock Holmes

Offline uprising

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Re: TH350 Problems
« Reply #21 on: December 02, 2019, 02:43:53 AM »
Thx @irish_alley
My hope is that they only changed the cabin and the wheelebase etc. is the original from the K10.

Before i will check the leakage of the transmission i have to change the radiator :-X

Btw: Does somebody has an emblem for my chevy? It costs 120 in germany.
« Last Edit: December 02, 2019, 04:40:07 AM by uprising »

Offline uprising

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Re: TH350 Problems
« Reply #22 on: December 04, 2019, 10:34:25 AM »
dang it...
Today i took a look into my garage and below the truck is a puddle of transfluid. And the trans isnt shifting. I switch to R, D and L but the truck isnt moving. Vacuumproblem or fluidproblem? How can i check the vacuum?

Offline Irish_Alley

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Re: TH350 Problems
« Reply #23 on: December 04, 2019, 11:37:50 AM »
could be it wont move due to the trans fluid being too low
If you cant tell yourself the truth, who can you tell it to?~Irish_Alley

When you have eliminated the impossible, whatever remains, however improbable, must be the truth ~Sherlock Holmes

Offline uprising

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Re: TH350 Problems
« Reply #24 on: December 04, 2019, 12:42:26 PM »
I measured in cold and the fluid is much more the  Hot. But to be on the save side i will check when engine is running. Any idea, how to check the vacuum?

Online bd

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Re: TH350 Problems
« Reply #25 on: December 04, 2019, 01:23:09 PM »
Describe how you have been checking the fluid level, please.  A vacuum issue will not cause the symptoms you describe, but low fluid level will.

You need to take the time to carefully inspect the transmission and find exactly where fluid loss is occurring.  Guessing and conjecturing will get you nowhere productive in a hurry.
Rich
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In other words... if people learn by making mistakes, by now I should know just about everything!!!
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Offline uprising

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Re: TH350 Problems
« Reply #26 on: December 04, 2019, 01:34:32 PM »
I just checked the oil with a cold engine. Pull out the dipstick, clean it up, push back in and pull again. The lower is much over the hot line. I have to measure again with a running engine. I can not run the engine until it is hot because the truck stands in my garage!
I think the fluid comes out of the oilpan. I got my new pan and the new gasket and i will change it again. Also i will check the filter.

Which symptoms do i habe if the vacuum has some problems?

Online bd

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Re: TH350 Problems
« Reply #27 on: December 04, 2019, 02:15:35 PM »
FYI - The engine MUST be running with the transmission in park (preferred) or neutral with the emergency brake firmly set (for safety) in order to accurately check the fluid level. 

Vacuum problems (such as low-to-zero vacuum) will cause a late, hard shift.  This occurs because the modulator valve interprets low engine vacuum (aka, high intake manifold pressure) as an open throttle, mimicking vehicle acceleration.  Zero engine vacuum signals wide-open throttle, for instance, times when maximum power is demanded from the engine during hard acceleration.

Look over the transmission carefully before removing the oil pan to determine the actual source of the fluid leak.  This could save you significant time, expense and frustration.
Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline Irish_Alley

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Re: TH350 Problems
« Reply #28 on: December 04, 2019, 04:56:59 PM »
also make sure to torque the trans pan bolts to the right specs. you would be surprised at how many times they get too much tq or not enough and will cause a leak
If you cant tell yourself the truth, who can you tell it to?~Irish_Alley

When you have eliminated the impossible, whatever remains, however improbable, must be the truth ~Sherlock Holmes