Downshifting not positive

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May 30, 2010 | 11:22 AM

emgee

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Tuned

Joined: Aug 2004

Posts: 399

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From: Winnipeg Canada

Downshifting not positive

When I downshift from 4 to 3 on my granny trans I sometimes encounter some resistance in the neutral position. It feels like I've hit the top right corner in the intersection, if you get what I mean, and I have to fiddle a little to get it into third. Any ideas on what's behind this; is there something that can be adjusted on the 3-4 fork, gate or reverse fork? I think it should be a little more positive downshift.

May 30, 2010 | 02:45 PM

ctubutis

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From: Denver Metro Area, CO

Try double clutching, see if it helps.

May 30, 2010 | 03:15 PM

emgee

Thread Starter

Tuned

Joined: Aug 2004

Posts: 399

Likes: 1

From: Winnipeg Canada

You're right, it helps and that's what I normally do (did it for years in my old '55 Chevy). I was wondering if there was something else that would be a more permanent fix.

May 30, 2010 | 08:29 PM

Rogue_Wulff

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From: Lost

How long has it been since the trans oil was changed? If you have no idea, then change it.

May 30, 2010 | 09:30 PM

ctubutis

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From: Denver Metro Area, CO

My personal suspicion is the synchros, my T18 does the same thing (replaced its fluid about
1.5 years ago when I rebuilt its engine). Rebuilding the tranny is on the wish list.

May 30, 2010 | 09:53 PM

Rogue_Wulff

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From: Lost

Hey CT, you might want to give this a try, it's a trick I picked up around the racetracks. Use a 50/50 mix of 90W and ATF in the trans. They claim it helps when the snycros start getting a bit worn. The ATF also helps the oil circulate a bit quicker, reducing the initial wear issue. Many people swear this mix will extend the life of trans that use 90W, whether it's used for regular driving or or for the vigors of road racing.
It really makes a huge difference in cold weather, as the trans will shift much easier.
It all stands to reason, since newer manual trans call for ATF as their sole source of lube.

May 30, 2010 | 10:02 PM

emgee

Thread Starter

Tuned

Joined: Aug 2004

Posts: 399

Likes: 1

From: Winnipeg Canada

The oil was changed about one month ago after the shifter was rebuilt and the oil was 80/90 gear oil. Your idea about the lighter oil mix sounds interesting. I'll seriously think about giving it a try.