Choosing the right clutch

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   If you are reading this, you might be in the market for a new clutch, and if so, you may have discovered there are many options. This segment was put together to help you choose the right one.

   There are many things to consider. First, it is important that you learn a little something about a clutch. What it is, what it does and why one clutch might be considered "better" than another.

   When people ask us for advice, we often hear the phrase "I just want the best clutch you have". Most customers believe that if one clutch has a higher power rating than another, that it somehow means it is better. That is not necessarily the case.

   There are several reasons you might need to upgrade your clutch. You have increased the horsepower and torque of the engine, you may exceed the recommended towing capacity or the truck, or a combination of both. There is also the group of people who build up their trucks for competitions like sled pulling or drag racing.

   So when you have people who just drive their trucks, people who work with their trucks and people who play with their trucks, you come to realize that they may all need different types of clutches. So the question is not "which is your best clutch?" it becomes "which clutch is best for my application?".

   So do this. First figure out how much power you truck has. This may not be as easy as it sounds, because, unless you have had your truck on a dynamometer, there will be some guess work involved. It is important to get as close as you can. Many people don't realize that you can over-clutch a system. A clutch designed to hold 550 hp may not act right in a truck that only puts out 350 hp to the rear wheels. We often hear people say that they "might" add more power in the future. Realize that if you choose a clutch based on that, and you don't upgrade later, you might end up with parts you're not happy with.

   Next. Decide what you want to do with your truck. Is it just a daily mode of transportation? Do you do any towing with it, if so, to what degree? Do you want to compete with it, if so how often? What size is your truck? Is it 2 or 4 wheel drive? Be specific. These are all important factors.

Here are some general rules:

• The hp rating of the clutch should match or slightly exceed the estimated hp of the truck

• Any truck used for competition sled-pulling should use an SFI approved multi-disc clutch.

• Trucks that regularly tow 15,000 lbs or more should use a double disc clutch designed for the street, regardless of the hp level.

• Trucks that are above the 450 RWHP which are used primarily for towing should use a street double disc. A full metallic single disc clutch is likely to engage too aggressively, especially on 2WD trucks.

• High torque clutches often incorporate metallic linings which may cause an aggressive engagement. This may be even more apparent when towing.

• Performance or high torque clutches may feel, drive or sound different than the factory system.

   Remember, when vehicles are modified beyond their factory specifications or used above the factory limitations, to the point where a performance clutch is necessary, things are going to feel different. By choosing the right clutch for your application, you can minimize these effects. However, some of the differences in how a clutch feels or sounds may be necessary to make the clutch hold and last.

Here are some unreasonable requests:

•  My truck puts 800 hp to the ground and I drive it every day and I want a clutch that doesn't push hard.

• My truck only has 400 hp, so I just need a single disc clutch, but I want to sled pull once in a while.

• I pull 20,000 lbs every day but I can't afford a double disc clutch. How many miles do you think I can get out of a single disc clutch?

• This is the last clutch I ever want to put in my truck.

   You need to realize that each clutch has limitations and that clutches that are built to hold extreme horsepower may not be the easiest clutch to drive on the street every day. So, as I said before, you need to decide what you want to do with your truck and understand that you are responsible for some of the consequences of trying to do too much.

   When you are buying a clutch, keep one thing in mind. No clutch is indestructible. No matter who made it or what it is rated for, you can destroy it in a hurry if you don't use it properly. So if you are careful when choosing it and reasonable when using it, you can get the most out of your clutch.