We enjoy all Mopar muscle cars, but particularly enjoy driving vehicles equipped with manual transmissions. There's just something about the synchronized performance of the arms, legs, mind, and automobile that results in the perfect power shift, which simply cannot be duplicated by an automatic transmission. So if you're lucky enough to get to row through the gears of your Mopar, you certainly don't want to miss that feeling because your car has transmission problems. And although the A-833-especially the early big-bearing and 18-spline Hemi units-are pretty tough, choosing the proper fluid can have a definite impact on the life of your transmission.
We've recently had a couple of letters and several questions on our web forums regarding running automatic transmission fluid (ATF) in the A-833 manual transmission, so we decided to give you the facts about this subject and let you decide what lubricant is correct for your application. From the factory, the majority of early Dodge, Plymouth, and Chrysler products equipped with the A-833 transmission had hypoid gear oil installed. And though we've heard a rumor that some late-'70s trucks had ATF installed from the factory, we have a feeling this is based on a technical service bulletin issued by Chrysler instructing that dealer mechanics try ATF if a truck owner was experiencing hard shifts.
While automatic transmission fluid does act as a lubricant, you must remember that it is a hydraulic fluid as well and lacks the additives required by the shearing (hypoid) action of helically cut gears like those in the A-833. ATF is also thinner than gear oil, and we've seen it ôfindö leaks anywhere a seal or tolerance is marginal. We called Jamie Passon over at Passon Performance who verified that ATF lacks the cushioning effect of hypoid gear oil and would cause premature wear of the synchronizers.
1 The A-833 four-speed manual...
1 The A-833 four-speed manual transmission has been around for a long time, coming in various configurations including those with both cast iron and aluminum cases, and overdrive high gears. If you’re lucky enough to have a four-speed equipped Mopar, you want to keep it shifting smoothly with the correct lubricant.
We agree with Passon's recommendation that good 80W90 weight gear oil is the lubricant of choice for most A-833 applications, and we've also had good luck with synthetic lubricants like AMSOIL Severe Gear. Engine lubricants and ATF may seem to offer an advantage, but you'll end up damaging the internals of the transmission, which can get expensive quick. So while it can be tempting to use the next trick someone tells you about, like using ATF in your four-speed, it's definitely not worth the risk of potential damage.
2a Many popular Mopars were...
2a Many popular Mopars were equipped with the A-833 four-speed, and we’ve heard of several tricks to make them shift better like running ATF or even motor oil in the transmission...
2b ...with the proper equipment...
2b ...with the proper equipment pulling the transmission is a pain, so we prefer to stay away from these tricks and use hypoid gear oil.
3a ATF doesn’t contain the...
3a ATF doesn’t contain the additives required by the shearing action of helical cut gears and is a poor choice for your muscle car’s manual transmission...
3b We recommend using ATF...
3b We recommend using ATF for its intended purpose, in automatic transmission applications like the 727 and 904.
4 A quick call to the experts...
4 A quick call to the experts at Passon Performance verified our opinion that a good 80W90 gear oil with hypoid additives is a great choice for the Mopar A-833 manual transmission. Passon also offers their own gear oil with a 50 weight equivalency, but still with the proper additives for Chrysler manual transmissions.
5 AMSOIL offers great synthetic...
5 AMSOIL offers great synthetic alternatives for all types of lubricants, and we’ve had good luck with their gear oils. Either way, stay away from ATF or other tricks, and only utilize quality hypoid gear lubricant in your Mopar four-speed. mm