FAQ

Yes we will be happy to help you make the right driveshaft choice but first we will need to know the dimensions of your application and also more information about the vehicle. Please select the appropriate measuring diagram for your vehicle and print it out so that you can have it with you under the vehicle as you do the measuring. After you have measured please email or call with those dimensions so that we can accurately recommend which driveshaft will be best for your vehicle. Click here to find the right diagram.

In most applications the minimum is 3/4 inch and more than 1 inch is not necessary. This is measured with the rear suspension supported on safety stands or with the rear end on the ground.

You may not save anything and in fact it may cost you more to do it that way. All Denny's Driveshafts are priced as a complete package. The cost of the slip yoke is factored in at an amount that is less than what you would pay to buy it separately. If you bid for the slip yoke on an ebay auction or if you select it as a "buy it now", your cost plus shipping it to you and then shipping it to us is almost always going to be more than it would have been if we had supplied the whole driveshaft including the slip yoke. The only way that it may save you money is if you purchased an expensive chrome moly slip yoke and paid less than half of what it normally sold for. Please call for the adjusted cost if you have a slip yoke you want us to use on your order.

A common mistake that is made when measuring is to measure the rear u-joint caps instead of measuring the pinion yoke. This is most common on Ford rear ends where a 1 1/8 inch cap diameter is found at the yoke saddles. Unfortunately someone has installed a u-joint with 1 1/16 inch caps. Always measure the pinion yoke.

1310 series and 1330 series should be tightened to 17 ft/lbs and 1350 series to 20 ft/lbs. You should never tighten the nuts on any u-bolt excessively. This will cause the cap to distort and the u-joint will fail prematurely.

This is usually the case when a u-bolt style pinion yoke is used. The pinion yoke is not the problem the overtightening of the u-bolt is the cause of the failure. You may find that every time you change the damaged rear u-joint you will find that one or both of the journals or caps that are under the u-bolts are destroyed and the ones that are pressed into the shaft are still in good shape. You did it to yourself! 17 ft/lbs for 1310 & 1330 series and 20 ft/lbs on the 1350 series. Click to see Photo

Yes. We will need your slip yoke to balance your driveshaft correctly.

No. We cannot build and balance a driveshaft correctly without u-joints.

There are many reasons. If you are using a stock driveshaft in a racing application then you already know the answer. Stock shafts should never be used for racing. If you had a driveshaft built by a driveline shop and it has broken or twisted the tubing then you should take it back to where you bought it.

They apparently built your driveshaft with tubing that was similar to stock driveline tubing or possibly selected a tube diameter or thickness that was not correct for your application. Just because the shop builds dump truck shafts does not mean it can handle the requirements of a race car.

This is a common problem and many times this seems like an inexpensive way to make it fit better but this type of fix should be avoided. We never recommend installing a longer slip yoke when the shaft is actually too short for the application.

Some transmission slip yokes are available with a longer barrel but they were designed longer for a specific application and not for the purpose of extending a shaft. Using one on a driveshaft that is actually too short for the application can lead to vibration and output shaft bushing failure. In extreme cases the internal spline can twist and bind up the slip movement. Don't do it!

No. The correct way to lengthen a driveshaft is to remove both weld yokes and install a new tube of the proper length

Seems like a dumb question but actually it is a very good question. This is a question that should be asked more often but is almost never asked until someone breaks the grease fitting off in the u-joint. You don't need to tighten the fitting as if you were tightening lug nuts!!!! These things can break and they will break if tightened too much. The question now is how much?? We use a simple nut driver (looks like a screw driver with a socket on the end) to install and tighten grease fittings. No ratchets, no breaker bars, no impact guns.

You DO NOT NEED much more than a snug fit and that fitting will stay put for a million miles. The threads on the fitting are tapered like a pipe thread so it is going to put up some resistance as you screw it in. There is absolutely NO GOOD REASON to bury that fitting into the u-joint by tightening it until the hex on the fitting comes in contact with the u-joint body. Don't do it because it will break!!! Remember a hand tight snug fit and you're done. There will be some threads exposed and that is perfectly acceptable. Enough said!