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Shifting without clutch

A trucker friend of mine says that in a synchronized transmission we really only need the clutch for 1st and reverse. So I have been practicing on my new 2009 outback and I am able to mostly upshift and downshift without the clutch. I want to make sure this is ok as long as I am not grinding the gears and if this prolongs the life of the clutch.

Ask your trucker friend if he will give you something in writing stating that he will pay for any future transmission repairs.
In the event any transmission problem surfaces during the warranty period, should I dare even ask if you’re going to tell the dealer and Subaru of America what your shifting habits are like leading up to any problem?

Considering the dubious history of Subaru synchronizer fitment on the gearsets, etc. and the fact the synchronizers are made of brass eventually this habit may cause problems that will catch up with you.

If you don’t abuse the clutch it should last for a long time so my opinion is to ignore the trucker friend and stop this ill-advised habit.

You are correct when you say it will prolong the life of the clutch.

But that isn’t the whole story. You will be shortening the life of the synchronizers in the transmission.

Clutches are far cheaper than synchronizers to fix/replace. Is that the way you want to treat your new 2009 Outback?

Knowing how to shift the clutch so you can do it in an emergency is a good thing. Doing it as a routine way of shifting will lead you to some expensive repairs down the road.

Thank you very much that answers my question. Are there different transmissions in larger commercial trucks that make this OK to do or is my trucker friend running the same risk as I am as far as synchro wear?

Most truckers have old beaters because they learn bad habits driving their trucks and apply them to their cars. What kind of car does your friend drive? What is the overall condition of his personal vehicle? This should give you a good indication of the value of his advice.

Commercial truck transmissions don’t have synchronizers, so the truck drivers must synchronize the engine speed with the transmission manually. However, synchronizers are not the only difference between your transmission and your friend’s truck transmission. If your trucker friend is floating gears correctly, he can get away with it. I hope he owns his own truck. If he ruins a company truck’s transmission, they will know why, and they will blame him.

My Buddy has a brand new international truck and he takes good care of his vehicles. It hink you hit is on the head in the fact that there are no synchronizers to wear out and either it shifts with the right RPM’s or it doesn’t. I won’t be playing trucker with my new care anymore.

Thanks for your time!

You can shift safely without doing any damage to the tranny without using a clutch…BUT it has to be done perfectly. One messup and you’ll start grinding gears. Make a few messups and you’re looking at a new/rebuilt transmission. 2-3 clutches for the life of a vehicle are a LOT cheaper then just one tranny rebuild.

Another difference is engine speed. Compare the RPMs a diesel turns with what a gasoline engine is turning. That all translates to how fast those gear teeth are turning too.

And speaking of truck drivers and transmissions, ever consider how many truck transmissions “need a little work”?

My late father in law owned 2 businesses; a masonry company and a small trucking company.
He used GMC trucks, contracted to haul rock and grain, and his biggest complaint was drivers tearing up the transmissions; which he had to pay ($$$$) for of course.

Your trucker friend’s job is driving, he has many hours of practice to perfect his technique. He may be great at it, but that’s still no reason to do it. There’s no upside, only major $$ downside.

Current Fuller, Spicer, Clark and New Process truck transmissions use syncronizers on forward gears. Sometimes they are called clutch gears, sometimes pre-selecters. Farm tractors are non syncro. Early automobiles were non-syncro. I was forced to learn to shift Case and Massey tractors without the clutch to pull heavy trailers on the road. Many truck drivers prefer not clutching with no apparent damage with upwards of a million miles on the transmission. But when forced to drive a car or light truck without the clutch the syncronizer can be felt dragging and it seems certain that the life of the transmission is shortened when driving clutchless. Just MHO.