6th gear install query
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From: Norn Iron
6th gear install query My box was built years ago by SixSpeedsInc, no issue there. It's a regular F-Body T56, albeit with 30T mainshaft.
But they also installed what I think are Vette 5th and 6th, but still normal 0.74 and 0.5 ratios, double cone synchros.
The box was taken apart to install new blockers a few months back by a guy local to me as I was too lazy.
I'm rebuilding it now with faceplated gears 1-4
In the picture, where the 5/6 shaft mates to the main cluster, and where 6th gear will reside.
When I place these parts together there is about 35 thou endfloat with 6th gear. It's as if there should be a shim or spacer behind the gear ?
The synchro teeth on 6th were also badly chewed up, which makes me think there has always been this endfloat
5th by comparison has about 10thou end float
I assume there is a shim missing ?
But they also installed what I think are Vette 5th and 6th, but still normal 0.74 and 0.5 ratios, double cone synchros.
The box was taken apart to install new blockers a few months back by a guy local to me as I was too lazy.
I'm rebuilding it now with faceplated gears 1-4
In the picture, where the 5/6 shaft mates to the main cluster, and where 6th gear will reside.
When I place these parts together there is about 35 thou endfloat with 6th gear. It's as if there should be a shim or spacer behind the gear ?
The synchro teeth on 6th were also badly chewed up, which makes me think there has always been this endfloat
5th by comparison has about 10thou end float
I assume there is a shim missing ?
6th gear roller bearing has a .035" washer at both ends. Those do not set endplay however. Compare it to a known good gear. Check for wear at the gear/ synchro thrust surface and tapered rear mainshaft bearing inner race. Set countershaft and extension preloads correctly. Done.
Thread Starter
9 Second Club
Joined: Nov 2003
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From: Norn Iron
The washers at the needle roller is purely to protect the bearing itself and these sit internal to the gear anyway.
Are you trying to suggest the gear itself is worn ? It will be replaced anyway as synchro teeth are chewed up, but they sent me the wrong gear and I'm waiting on the correct one.
I'm just piecing things together to ensure everything is ok while I wait on it.
All bearings are fine, and preloads/cluster/shaft endplay are all fine.
The tapered synchro cone surface is fine also.
But this 5/6 setup isnt normally fitted to this trans, so wondering if they've just made a mistake when piecing it together, which in turn has led to the wear in the synchro teeth.
how much endfloat should each gear have ?
Are you trying to suggest the gear itself is worn ? It will be replaced anyway as synchro teeth are chewed up, but they sent me the wrong gear and I'm waiting on the correct one.
I'm just piecing things together to ensure everything is ok while I wait on it.
All bearings are fine, and preloads/cluster/shaft endplay are all fine.
The tapered synchro cone surface is fine also.
But this 5/6 setup isnt normally fitted to this trans, so wondering if they've just made a mistake when piecing it together, which in turn has led to the wear in the synchro teeth.
how much endfloat should each gear have ?
Correct on the washers.
I am saying that's where wear would potentially have an issue. However a visual check and I would have moved forward on assembly.
They sent the wrong one or you ordered for a Camaro?
.010 is fine. .035 is fine. The one you are fretting over fits to two shafts, each with an installed part as the thrust washer for the gear. Makes perfect sense for it to have extra tolerance. No need to chase a tolerance needed in engineering and not in a rebuild. Further, it is a dynamic number if the bearing endplay is loose due wear.
I am saying that's where wear would potentially have an issue. However a visual check and I would have moved forward on assembly.
They sent the wrong one or you ordered for a Camaro?
.010 is fine. .035 is fine. The one you are fretting over fits to two shafts, each with an installed part as the thrust washer for the gear. Makes perfect sense for it to have extra tolerance. No need to chase a tolerance needed in engineering and not in a rebuild. Further, it is a dynamic number if the bearing endplay is loose due wear.
Thread Starter
9 Second Club
Joined: Nov 2003
Posts: 13,616
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From: Norn Iron
No, they sent me the wrong one I explained to them what the trans was, the alterations, I sent them photos of my entire 5/6 assembly in detail showing 6th gear and how different it was from a normal Camaro.
There is no bearing endplay
There is no bearing endplay
