Manual Transmission T56 | T5 | MN12 | Clutches | Hydraulics | Shifters

can't downshift from 6th to 5th

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Old Aug 29, 2008 | 09:20 AM
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Default can't downshift from 6th to 5th

my 99 ss just recently purchased will not downshift from sixth to fifth anymore. It worked fine when i bought it, i just installed a diablosport tune but i don't think that would have anything to do with it. It goes into fifth fine from fourth and has no problems in any other gear, i just can't go straight sixth to fifth. I have to go to fourth then to fifth, any help would be appreciated!
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Old Aug 29, 2008 | 10:01 AM
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Sounds like synchro issue. My 99 SS had abn issue with 5-6 too. I had to have new syncros installed for the 5-6
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Old Aug 29, 2008 | 05:19 PM
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should i worry about if it goes into gear fine, just can't downshift?
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Old Aug 29, 2008 | 05:22 PM
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my car doesn't shift from 6th to 5th either. i took it o a tranny shop and they said it was normal for my tranny. its a safety stop so that you cant accidently throw it in neutral.
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Old Aug 29, 2008 | 05:22 PM
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not all t56's are like that but i guess a lot of them are.
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Old Aug 29, 2008 | 05:27 PM
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Yeah mine does the exact same thing
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Old Aug 29, 2008 | 06:00 PM
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Never heard of some T56's doing that and others not. I've had two different tranny's and neither had a "lockout". The first one had issues downshifting into second, but upshifted just fine. I would think a synchro is going out.
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Old Aug 29, 2008 | 06:49 PM
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There's no lock out on the T-56 for 6-5.

I was just ripping thru the gears earlier today and did a few drops to fifth to do some low speed passing 4th is reserved for some play and 3rd is the serious highway roll gear.

You have a syncro issue at the least.
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Old Aug 29, 2008 | 07:05 PM
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Mine has no issues with the 6th-5th downshift either.

Whoever said its designed like that doesn't know their *** from a hole in the ground.
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Old Aug 29, 2008 | 07:40 PM
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The only lock out a T-56 has is for 2 and 3 during skip shift and the reverse lockout. Something is WRONG with your transmission if 6-5 is not working. Could be keys, syncros won't know until it's taken apart.
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Old Aug 30, 2008 | 12:21 AM
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I've seen alot of shift fork pad wear cause strange 5/6 issues before. You wont know untill you tear the trans apart & check it out. Something is obviously not right.
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Old Aug 30, 2008 | 12:27 AM
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Ah **** I was hoping this was a common issue, looks like I have to take the trans apart when I get a chance. Thanks for clearing this issue up
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Old Aug 30, 2008 | 12:35 AM
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well **** how much does getting it fixed cost?
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Old Aug 30, 2008 | 12:45 AM
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Well while your there might as well rebuild it IMO. Heck even upgrade with billet keys bronze shift fork pads etc.....
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