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Mygoobers Samba Member
Joined: November 25, 2012 Posts: 42 Location: Florida
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Posted: Tue Jul 26, 2016 8:25 am Post subject: Automatic transmission problem |
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I have a 68 automatic. The problem is the trans doesn't like to drop into drive unless your like on the gas or you burp the pedal. Once in drive, if you give too much gas it bangs down to second. Once the trans is hot , it basically won't drop into drive. Any help would be greatly appreciated |
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Mike Fisher Samba Member
Joined: January 30, 2006 Posts: 17974 Location: Eugene, OR
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Posted: Tue Jul 26, 2016 9:54 am Post subject: Re: Automatic transmission problem |
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Chapter 8 Automatic Transmission in the Type 3 Bentley manual has a trouble shooting guide & rebuilding instructions. Search (under the Forums tab) for 'automatic transmission problems' in Type 3 Forum turned up these previous threads that might be helpful.
http://www.thesamba.com/vw/forum/search.php?search..._chars=200 _________________ https://imgur.com/user/FisherSquareback/posts
69 FI/AT square Daily Driver
66 sunroof,67,70,71,71,71AT,72,72AT,73 Parts
two 57 oval ragtops sold
'68 Karmann Ghia sold
Society is like stew. If you don't keep it stirred up you end up with a lot of scum on the top! - Russ_Wolfe/Edward Abbey |
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Multi69s Samba Member
Joined: January 24, 2006 Posts: 5369 Location: Lefty, CA
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Posted: Wed Jul 27, 2016 12:59 am Post subject: Re: Automatic transmission problem |
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When was the last time you dropped the pan and cleaned the strainer? Also check the hose that goes between the modulator and the intake manifold. It needs to be snug and no pin holes. The burping the throttle and it kicking down sounds similar to not enough vacuum to the transmission. Get some clean fluid in it check the hose and it may need the modulator adjusted. For giggles you might disconnect the kick down switch. If it is out of adjustment it might do this as well. _________________ 69 road Bug 2110
73 Squareback - 2L, T4, Automatic W/ AC
Gone, but many fond memories 69 Baja Bug 2010 - 5 Rib Bus Transaxle
Gone but not forgotten 72 Baja Bug 2010
My builds
T4 into Squareback http://www.thesamba.com/vw/forum/viewtopic.php?t=458944&highlight=
Auto Trans Rebuild http://www.thesamba.com/vw/forum/viewtopic.php?t=516066&highlight=
AC in Squareback https://www.thesamba.com/vw/forum/viewtopic.php?t=...highlight= |
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Mygoobers Samba Member
Joined: November 25, 2012 Posts: 42 Location: Florida
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Posted: Wed Jul 27, 2016 6:41 am Post subject: Re: Automatic transmission problem |
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Thanks bi just ordered a Bentley book. To help me out. What will happen if I disconnect the switch ?? |
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KTPhil Samba Member
Joined: April 06, 2006 Posts: 34023 Location: Conejo Valley, CA
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Posted: Wed Jul 27, 2016 8:56 am Post subject: Re: Automatic transmission problem |
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If the switch is working normally, and you floor the pedal all the way to actuate it, it keeps it in a lower gear longer as you accelerate. Similarly, if you are cruising and then stomp the pedal all the way, it will down shift faster and at a higher speed. So either way it gives you a bit more power when you need it. You could achieve the same effect manually shifting the selector lever, but this makes it a no-brainer operation.
So disconnecting it will just make it upshift sooner on full throttle, and not down shift at as high a speed (also at full throttle). So no harm is done.
On the other hand, if it is misadjusted or broken, disconnecting it might change your symptoms and then you have a clue where the root cause of your problem is.
Easiest way to disconnect it is to remove the fuse from the black plastic fuseholder between it and the coil. No dangling live wires that way. |
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Mygoobers Samba Member
Joined: November 25, 2012 Posts: 42 Location: Florida
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Posted: Wed Jul 27, 2016 9:23 am Post subject: Re: Automatic transmission problem |
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Any thoughts of why it won't shift into drive as it gets warmer ?? |
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KTPhil Samba Member
Joined: April 06, 2006 Posts: 34023 Location: Conejo Valley, CA
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Posted: Wed Jul 27, 2016 9:50 am Post subject: Re: Automatic transmission problem |
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If it changes with temperature than it must be fluid related (I know, "duh"). I would do the "easy/cheap" stuff and work my way up the budget. Change the fluid and filter, make sure everything is clean inside, change hoses, and then move on to checking hydraulic pressures.
There is a good thread on rebuilding these... some of the steps above may be covered in it.
http://www.thesamba.com/vw/forum/viewtopic.php?t=516066
Also check this thread:
http://www.thesamba.com/vw/forum/viewtopic.php?t=510833 |
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Mygoobers Samba Member
Joined: November 25, 2012 Posts: 42 Location: Florida
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Posted: Wed Jul 27, 2016 9:59 am Post subject: Re: Automatic transmission problem |
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Thanks for all your help |
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Multi69s Samba Member
Joined: January 24, 2006 Posts: 5369 Location: Lefty, CA
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Posted: Thu Jul 28, 2016 2:13 pm Post subject: Re: Automatic transmission problem |
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Does reverse work fine, even when warm? If so, your are probably looking at a pressure issue. As the trans gets warm, the viscosity of the fluid will change a bit, so if your pressures on the low side to begin with, then as the fluid heats up, you may have a lower pressure. causes for this change, but not limited to: old fluid, clogged strainer, bad hose to the modulator, modulator needs adjusting due to internal wear.
These are all things that can be checked without major work. However, to adjust the modulator, you need a set of gauges like this
http://www.ebay.com/itm/OTC-Transmission-Engine-Oi...mp;vxp=mtr
Also, an Allen wrench that is in new condition. The screw in the modulator is brass or similar, and a bad Allen wrench can round it out. _________________ 69 road Bug 2110
73 Squareback - 2L, T4, Automatic W/ AC
Gone, but many fond memories 69 Baja Bug 2010 - 5 Rib Bus Transaxle
Gone but not forgotten 72 Baja Bug 2010
My builds
T4 into Squareback http://www.thesamba.com/vw/forum/viewtopic.php?t=458944&highlight=
Auto Trans Rebuild http://www.thesamba.com/vw/forum/viewtopic.php?t=516066&highlight=
AC in Squareback https://www.thesamba.com/vw/forum/viewtopic.php?t=...highlight=
Last edited by Multi69s on Thu Jul 28, 2016 2:27 pm; edited 1 time in total |
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Mygoobers Samba Member
Joined: November 25, 2012 Posts: 42 Location: Florida
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Posted: Thu Jul 28, 2016 2:22 pm Post subject: Re: Automatic transmission problem |
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Yes reverse still works |
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raygreenwood Samba Member
Joined: November 24, 2008 Posts: 21521 Location: Oklahoma City
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Posted: Thu Jul 28, 2016 2:44 pm Post subject: Re: Automatic transmission problem |
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A couple of items as well.
As others have noted...probably fluid pressure related. Things that can also affect fluid pressure...of course it gets thinner as it heats up...and everything else expands as well.
Do a band adjustment.
Also check the differential oil to make sure its not ATF fluid pressure leaking into the the differential oil. I say this because if the governor seal is shot you could be having odd governor performance due to leaking fluid...with the bypass fluid leaking into the diff housing. Ray |
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KTPhil Samba Member
Joined: April 06, 2006 Posts: 34023 Location: Conejo Valley, CA
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Posted: Thu Jul 28, 2016 2:50 pm Post subject: Re: Automatic transmission problem |
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raygreenwood wrote: |
...you could be having odd governor performance due to leaking fluid...with the bypass fluid leaking into the diff housing. Ray |
...and soon destroying it from improper lubrication! |
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