Some kid I know drives a '90 5.0 Mustang, and after he destroyed his transmission, he opted for a new one with no synchronized first gear - so at stops sometimes, it wont go immediately into first without pulling it into second before.

I was wondering, why go with a non-synchronized first gear? I cannot think of any real benefits, besides maybe saving a couple dollars....

 

Well you said it right there! Those drivers never think with their head on straight!

to be honest, i really have no idea why, never even heard of a non-synchronized 1st gear

 

All I can come up with is that in most cars, the actual gears are always in constant mesh, and the synchronizers only decide which pair of gears to connect to their shaft. With trucks, because they have so many gears, it's noticeably more efficient not to have all of the gears in mesh all of the time. So with the "crash-box," you HAVE TO double-clutch, or you will not be able to shift. The same holds true for racing cars—to gain the last couple percent of efficiency, only one set of gears is in mesh at any time, and you have to actually synchronize their speeds or you can't get it in gear. This makes the gearbox is stronger and more efficient than a comparable synchromesh one, and has less tendency to overheat.....correct?

However, we in this case are simply talking about first gear just not being synchronized....

 

Do you know what the trans was out of?

It is common on dump trucks and heavy trucks to have an unsynchronized first gear which is only intended for hauling starts, a creeper gear if you will. The Spicer T18a and New Venture 4500 have 6.32:1 and 6.34:1 first gears unsynchronized. There was some other ford trans from the 60s with a 7.x:1 ratio i believe.

I used to have a T5 in my CJ7 which had a very low first gear ratio which I used as a creeper gear. IOW, i always pulled out in 2nd. The T5 was used in a vast variety of different vehicles, but not all that heavy duty. I don't specifically know of any vehicles with an unsycho'd 1st gear T5.

Because you would never downshift to 1st in normal driving except for at a dead stop it shouldn't be a big deal. Even racing you'd never really downshift to 1st. Kind of the same deal as our reverse not being synchronized.

Are you sure the syncho wasn't just shot?

I probably just muddled this up more than i really answered anything. Sorry.

Brent

 

On the crash box thing, they are like a regular transmission except they have dog rings instead of brass synchronizers and the sliders usually have every other spline removed. You may or may not use the clutch to shift, but they are not a true clutchless transmission. My old Liberty prepped cast iron T10 was the best shifting transmission I have ever had, but they wear out pretty fast on the street. The teeth and sliders round off and then won't stay in gear until you have new dog rings welded on. Ironically for this discussion, my transmission had a synchronized 1st only, only half the slider was machined as it was designed for upshift of course. That transmission would go in any gear at any time. I accidentally pulled 2nd instead of 4th once at 7000 and let the clutch out....briefly...oh my.