PCA Southeast Michigan Region

Which transmission gear oil should I use?

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Which transmission gear oil should I use? 
Without a doubt, the best transmission gear lube to use in manual transmission cars appears to be Swepco 201. Normally, I don’t make blanket recommendations like these, but my customers simply swear by it. I’ve had many of them insist that the addition of Swepco 201 can forestall a transmission rebuild for several thousand miles. While I’m not exactly sure what magic stuff exists in the Swepco 201, I can
indeed tell you that it is the number one choice amongst our Porsche and BMW customers.

Particularly with the racing crowd, the Swepco oils have a somewhat 
legendary status. For more information and customer testimonials, check out this link in our Porsche Bulletin Boards: Click Here Be sure that you check with your owner’s manual first though – some special transmissions require a slicker, synthetic formula than the Swepco. Bad shifting habits that will hurt your transmission… Hmm, there are hundreds of things you can do that will hurt your transmission. I only really have space here to talk about a few though. Here are two of the worst: – Leaving the clutch pedal pressed in while at a stop light.

This one is both bad for your clutch and your engine. It places a load on the pressure plate spring and your throw-out bearing. In addition, it places forces along the center of your engine’scrankshaft, which can lead to premature wear of flange bearings in the engine. When you put your foot down on the clutch and leave it there, you are ‘stretching’ the spring that is used to control the clutch, and that spring then pulls or pushes on the crankshaft of the engine. Only doing this once and a while is fine, but repeating this over thousands of miles will cause both your engine bearings and your clutch to wear out prematurely. – Slamming your transmission into 1st gear. Let’s say you’re at a light, day dreaming about what you’re going to have for lunch. You don’t realize the light has changed,and someone honks at you from behind. So you super-quickly push the clutch inand slam your transmission into first gear. Crunch! This (as you might have suspected)is very bad for the transmission – even if you don’t hear it crunch. The transmission needs time to ‘spin down’ as you engage first gear.

Slamming it into gear right after you let the clutch pedal out is simply bad for it. Push the pedal in for a moment, and let the transmission ‘spin down’ a bit before you shift into first. Another trick is to shift into 2nd or 3rd prior to shifting into first gear – this will help spin the transmission down without grinding your 1st gear synchro. The same principle applies when shifting into reverse. Wait a few seconds after pressing the pedal down, before shifting into reverse. Improving a poorly shifting transmission… I won’t tell you how many people have talked to me about how they had their transmisison rebuilt (expensive), only to find out that the problems was actually 
with their shift linkage bushings. Very often on older cars, the shifting ability deteriorates as the years go by. While many people blame their transmissions 
and prepare for a full rebuild, their worries may be needless. In many cases, theshift linkage bushings have simply worn out and need to be replaced. Worn 
bushings can result in sloppy shifting, misplaced shifts, and grinding when engaging gears. Most people are amazed at the improvement that occurs when they replacetheir bushings. A mere $45 spent on new bushings is a heck of a lot cheaper than a $1500 transmission rebuild. Shift linkage bushings are different on every car, but the results are often the samewhen they are replaced – the transmission shifts a lot smoother. At a bare minimum, replace your shift bushings prior to having any major transmission work performed -that way you will eliminate them as a potential problem When you have all the bushings replaced, and the shifter adjusted, the car should show a remarkable improvement. If you are still having problems with shifting and grinding, you mightwant to check your clutch adjustment, or your motor and transmission mounts, orthe fluid level in your transmission. Myths and truths about short shift kits… One of the most popular additions to many cars is the installation of a short shift kit. The kit shortens the length of throw on the shifter, theoretically giving you the ability to shift faster.

Installation is relatively easy, and typically takes the better part of anafternoon. However, many people install short shift kits in their cars thinking that it will fix problems that they are having with their transmission. This will not solve any problems, and will in most cases make a poorly shifting car shift even worse. The reason for this is that with the short shift kit, the torque arm on the shift lever is much shorter, giving you much less ‘resolution’ on your shifter. It’s similar to having a gas pedal that onlytravels 1 inch over its range instead of 2-3 inches. You have less precision in how much throttle you want to give the car. In a similar manner, with the short shift kit youwill have less precision on where theshift rod is placed. It’s a wise idea to tackle thecore problems with your transmission (synchros, shift bushings), prior to the installation
of the short shift kit. Ironically, many people install a short shift kit onto a poorly shifting transmission, and then magically proclaim it ‘cured.’ In fact, in most cases, they didn’t fix anything with the transmission – the short shift kit is simply ‘muscling’ the transmisison into gear usingmore force and more leverage. The bottomline? Only install a short shift kit into your car if your transmission doesn’t have any shifting problems. Well, there you have it folks, part 2 of my tips and tricks on transmissions. Next week, I’ll finish off part 2 of my thoughts on water cooling systems, and how importanttheir maintenance is to the health of your car. Thanks again for your support!

Wayne R. Dempsey
Principal Owner of DriveWerks