'62 transmission question

[landrover67]

I have a 1962 Buick Special, original V6 and two-speed automatic transmission. Next year I am thinking about driving cross country, and would prefer to do it in this. However, when I am driving 65 mph, the engine has high RPM's because it only has two forward gears. Would it be wise to switch to a three-speed automatic for such a long trip like this? Does anyone have any trouble doing 75-80 mph with a three-speed? Hitting mph like that is pretty much impossible in my car. Would appreciate any info anyone could give on this question. Thanks!

-brian

PS Has anyone ever done a cross country trip in an old (25+ years) car? Any advice to give? thanks.

[NTX5467]

That two-speed automatic probably is the Dual-Path Dynaflow, which was a Buick-only creation. I don't recall those cars having terribly low (high, numerically) rear axle ratios. I suspect it should be somewhere in the 3.3 or so range, maybe even closer to 3.0. With the small tires and wheels, compared to something with larger tire sizes and such, it could make it more like a 3.73 comparatively speaking, but I still suspect it would run somewhere in the mid-2000 or so rpm range at normal 65mph cruising speeds.

If my suspicions are correct in the case of the cruise rpm level, then there should be no problems with any kind of long trip. Those compacts from GM back then all had 2-speed automatics in them anyway. None were "low speed" vehicles either, being limited more by engine power than rpm, typically.

Putting a three-speed automatic in there would solve nothing, but would let you have a lower low gear for better starting and low speed performance. You'd still have the same rear axle to contend with so cruise situations would not change. Only the newer overdrive automatics would lower the cruise rpm, BUT adding the .70 overdrive gear ratio on top of the 3.3 range (if that's the case) rear axle ratio would lower the engine rpm too much and make the car "gutless" until it downshifted out of overdrive--probably not helping fuel economy in the process either, only making it worse and less fun to drive. Plus, such a swap would mean lots of fabrication and engineering, maybe even some floorpan modifications to clear the larger transmission too.

So, see what your highway cruise rpm is first. Could be you're hearing noise from the engine fan or similar instead of a tightly wound engine--unless you're trying to cruise at 90+ mph. Might be something under the hood that is picking up a resonance that might go away if, for example, and engine bracket if fully torqued down. Maybe even exhaust noise?

Then, you can verify what the rear axle ratio is too. With those two pieces of information, you can determine "what's next" and "how much will it cost to change it".

Also verify that the automatic is operating correctly. It was a unique design due to the "dual paths" the torque would take through the transmission depending on the operational mode it was in. Might be something that is not "up to snuff" in there?

If there was an optional 14" tire/wheel combination for those cars, that would be a better choice to change and probably be much more cost effective too. You'd need to get the speedometer calibration altered to reflect accurate speed/distance with tne new combination, though. The larger diameter 14" tire combination would effectively change the rear axle gear ratio to a lower number for less rpm on the highway. Might not be much change, though, depending on how things compare. In that case, you'd still probably desire to maintain a stock look so it would still need to be whitewalls and such and not something white lettered and waaayyyy tooooo wide. Just some quality normal whitewall radials would probably be fine, or some repros . . . just depends on how you want it to look.

Just some thoughts . . .

NTX5467

[The Old Guy]

Buick Engineers were quite careful about gearing cars . Your V6 will run cross country just as it is with NO problem . I have driven OLD cars all over the USA, and although I did change the rear gears in my 40 ,I drove everything else the way they were designed, and have experienced no problems at all. That engine will run at 70+ all day long.

[Guest my3buicks]

I had a 61 Skylark, although it was the aluminum V8 it had the dual path tranny in it. It was a great travel car, surprising comfortable for a small car. I averaged 21 mpg with it when I would travel.

As far as traveling, you have to make sure your car is up to snuff before you leave. Proper maintenance is a must. Make sure all your belts, hoses are in good order along with other such items. Make sure your cooling system is in good condition. I always carry a spare fuel pump and water pump and alternator along with some other "goodies" just in case. You should also have your tools and "emergency" repair items along. "TAKE DUCT TAPE" I have traveled all over the Country over the years in Classic Buicks. I won't say I have never had a problem, but I have always been able to repair the car or get it home under it's own power. Another way to see it - How often do you see newer cars sitting along the road broken down? Get it ready properly, travel, and enjoy it, there's nothing like traveling in a vintage Buick.