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On both cars I won at auction, the 6 gear trannys were both worked over pretty good with rounded profile layshaft and lower gears for minimal drag, black delrin idler gears, etc... They are really smooth and free for a 6 gear trans. They both had the stock thrust bearings removed though in exchange for a regular single bearing (like a motor endbell bearing) with the id the same as the layshaft and two really thin washers on both sides of it. Does this make sense to anyone? Was this a "hop up" in the old days that people have heard others doing?

Far from a hop up, that won't work too well!

i don't see how that could possibly work............................

Very odd. Perhaps they were trying to lock the diff for some reason, and that's just the combo of parts that got the spacing right.

It "shouldn't" work. But it's probably better than dented balls and grooved rings. It may give the impression that the diff action is smoother, but there's probably still some friction.

The jammin kit I installed used a thrust bearing like the ones found on the older stealth slipper clutch. You can probably use that and the small thrust bearing washers (like small diff rings) to duplicate that setup.

regards,
highwayracer.

Ok, so this was some odd instance this one guy did to his cars. It does actually spin pretty free with the bearing and the washers though..

Is it a ball bearing or a bronze bushing they put in there? Motors come with both, I just assumed you meant a ball bearing! Bronze bushing would be ok I suppose but not as good as a thrust ball bearing, a normal ball bearing would be just stupid.

6-gear experts please correct me if I'm wrong, but the thrust bearing is essentially the key piece of the differential on these transmissions. Without this type of bearing – where the balls are making contact with the washers – there would be no true differential (counter rotation) effect. While the transmission will spin freely, without that type of bearing, the differential would either be too loose, locked or there’d be substantial friction, any of which would result in poor handling/performance.

you would be correct.

Bugle wrote:Is it a ball bearing or a bronze bushing they put in there? Motors come with both, I just assumed you meant a ball bearing! Bronze bushing would be ok I suppose but not as good as a thrust ball bearing, a normal ball bearing would be just stupid.

It's a ball bearing like ones in mod motors.

aeiou wrote:6-gear experts please correct me if I'm wrong, but the thrust bearing is essentially the key piece of the differential on these transmissions. Without this type of bearing – where the balls are making contact with the washers – there would be no true differential (counter rotation) effect. While the transmission will spin freely, without that type of bearing, the differential would either be too loose, locked or there’d be substantial friction, any of which would result in poor handling/performance.

The only thrust bearing which creates the differential action is the diff plates and balls in the spur gear. You could have nothing between the 2 top shaft gears and it would still be a differential, just wouldn't be too smooth. It's a similar function to the stealth slipper thrust bearing, they managed to get away with a bronze bush there.

But in call-911's case there's a ball bearing, might as well have a pack of washers there for all the good that will do.

Bugle wrote:

aeiou wrote:6-gear experts please correct me if I'm wrong, but the thrust bearing is essentially the key piece of the differential on these transmissions. Without this type of bearing – where the balls are making contact with the washers – there would be no true differential (counter rotation) effect. While the transmission will spin freely, without that type of bearing, the differential would either be too loose, locked or there’d be substantial friction, any of which would result in poor handling/performance.

The only thrust bearing which creates the differential action is the diff plates and balls in the spur gear. You could have nothing between the 2 top shaft gears and it would still be a differential, just wouldn't be too smooth. It's a similar function to the stealth slipper thrust bearing, they managed to get away with a bronze bush there.

But in call-911's case there's a ball bearing, might as well have a pack of washers there for all the good that will do.

I didn’t mean to imply that the thrust bearing is the entire diff, but rather a key piece as I mentioned. While similar in nature, unlike the Stealth slipper thrust bearing, the trust bearing in the integrated 6-gear design plays a bigger role as far as the diff goes. If there were no bearing at all, I wonder if you could even tighten the diff nut enough to keep it from slipping without over-stressing/bending the e-clip. On the opposite end, if you have solid filler in there, the diff would most likely be locked or at a minimum very restricted.

Just an additional $.02 ...

It'd pop the e-clip off and keep going til the gears were touching each other

Yeah it doesn't matter as much having extra friction there with a slipper thrust bearing application because the slipper itself has so much friction.. You'd want the least amount of friction with a diff.