Driveshafts and the components they are built of come in a dizzying array of sizes, shapes and descriptions. They are grouped into series based upon torque ratings (and other factors) and each manufacturer, not surprisingly, has it's own particular way of doing things. We have compiled some reference materials here to help you identify some of the more common driveshaft components and accurately measure your vehicle or equipment for a new or replacement shaft. There is so much more out there that time and space will not allow us to cover here. If you have questions concerning anything you see here or don't find anything that looks like what you have please call us!

U-Joint/End Yoke Series Identification

There are a myriad of universal joints and parts used in passenger cars, light trucks, medium and heavy duty trucks and industrial applications, transmitting power to make things move. We have tried to be as complete as possible but please call us if you don't find your style of parts! You will need to take a look at your parts to narrow down the options you see here.

Outside Snap Ring Joints & Yokes GM, Chevrolet, Ford, Jeep
Inside Snap Ring Joints & Yokes GM, Chevrolet, Dodge
Combination Universal Joints Jointing different series/parts
Bearing Plate Joints & Yokes Heavy truck, industrial, oilfield
Mechanics Joints and Yokes Industrial, oilfield, older Mack Trucks
Spicer SPL Joints & Yokes OE on International and others
Meritor RPL Series OE on Freightliner
Attaching Hardware Torque Specs U-Bolts, Strap & Bolt Kits

Measuring Driveshafts for Vehicular Applications

Identifying a series of parts is one thing, and correctly measuring a car, truck or piece of equipment for a new or replacement driveshaft is still another. All require a little basic knowledge to do properly and the accuracy of the measurements play directly on the fit of the parts or driveshaft. Here we will help you understand how and what to measure so we can build your driveshaft correctly the first time.

NOTE: All vehicular driveshaft measurements should be made with the weight of the vehicle on it's wheels - suspension loaded!

Points of Measurement The secret to measuring for a driveshaft is knowing the points to measure from and to - where to put the tape. The image below shows the end fixtures most commonly found in driveshaft application. Most automotive shafts feature a transmission slip yoke at one end and an end yoke at the other, while many industrial/oilfield shafts are flanged at each end. Keep in mind that all driveshafts must have a provision for "slip" (the ability to change it's length) somewhere in the shaft. In a truck or car, for example, the engine/transmission power plant is installed on flexible mounts while the rear axle is hung from the vehicle's suspension - everything is moving. The driveshaft must be able to accommodate this motion. This fact will help you understand the how's and why's of driveshaft measurement. Think of measuring for your driveshaft as simply measuring from point A to point B, with a point C tossed in there for a two-piece driveshaft. If you know where to place and read your tape for each of these three points you can correctly measure your car, truck or other application correctly.

Point A: The end of the driveshaft at the power source, usually a transmission. There are but three different types of fixtures here: automotive and light truck shafts usually have a transmission slip yoke at point A, though some have a fixed end yoke. Transmission slips do as they are named - the yoke is long and splined onto the output shaft of the transmission, providing the necessary slip for the driveshaft to work as the vehicle's power plant and suspension work. Fixed end yokes and fixed companion flanges are fixed by a nut or a bolt to the transmission shaft - no movement here. In these cases the slip is built into the driveshaft with a slip yoke/splined stub set of parts. (Remember a driveshaft must be able to change length as it operates!) In the image below, Point A is either the centerline of the u-joint cap (in the case of a transmission slip or and end yoke) or the face-of-flange (in the case of a companion flange. Please note that a transmission slip yoke should be set in it's operating position (0.75" off bottom) prior to measuring.

Point B: The output end of the driveshaft, usually at the axle. The axle will have a fixed end yoke or companion flange attached to the pinion. So, Point B is the centerline of the u-joint cap (for an end yoke) or the face-of-flange (for a companion flange) at the power output end of the driveshaft.

Point C: Driveshafts that run long distances must, in most cases, be sectioned into shorter pieces that require a center bearing (carrier bearing) to support the connection of the front and rear sections. Point C is the centerline of the bearing and is most accurately measured from the center of one of the two bolts that hold the bearing assembly in place. Carrier bearing ends consist of two or three components: the bearing itself is pressed onto a bearing stub. Some bearing stubs are long and used with forward-facing slip yoke on the rear driveshaft. Others are short and have a fixed end yoke or fixed companion flange, using a rear-facing slip yoke on the rear driveshaft. Automotive and light truck applications usually have the long bearing stub setup, while heavy truck's use the fixed yoke style bearing end. Refer to the image below for your bearing end style and heed the notes for each!

PLEASE NOTE: Parts shown in this image are representing a type of part, not your particular part. Your slip yoke or center bearing may not look just like the ones in the image but it will look like one of these part types. Identify the type of part(s) in your driveshaft and use the points of measurement for that type.

Measuring Driveshafts for Auxillary Equipment

Auxillary equipment driveshafts are measured a bit differently. In new installations the driving output shaft and the driven input shaft are just that: round keyed or splined shafts without any end yokes, flanges or other fixtures installed. In the image below we have used a power takeoff and a hydraulic pump as examples of auxillary components that may be truck mounted. Others include winches, product pumps, right angle gearboxes, etc. All are measured for driveshafts in the same manner: tip-of-shaft to tip-of-shaft. Measuring the diameter and key size of a round shaft or, in this image, the diameter and spline count of a splined shaft is necessary as well to have the right end fittings installed on the shaft when it is built. Please give us a call if you need help measuring for your auxillary equipment shaft requirements.

Use the Resources!

Use the U-Joint Identification section to ID your series of parts, then use the Measuring For Driveshafts section to accurately measure your car, truck or auxillary driveshaft. We'll be quite impressed when you call us to order a 1350 Series driveshaft at 54.5" C-C for your hotrodded Camaro!



Parts list, service and installation guides and more. Click to open the PDF file and use the table of contents on the left margin to navigate. We have included some of the most common reference books here. For a more complete listing please go to our Contact/Links page to access Chelsea's online library.

Chelsea PTO

Some parts lists and manuals are quite large PDF files and may load slowly, dependant upon your internet connection. Patience is a virtue.

270 Parts List 6-bolt hotshift for Allison
277/278 Parts List 10-bolt for Allison New World
340 Parts List 6-bolt heavy duty forward & reverse
442/489 Parts List 6/8 bolt single speed workhorse
823 Parts List 8-bolt extreme duty single speed
852 Parts List 8-bolt hotshift oilfield mainstay
863 Parts List 8-bolt extreme duty forward & reverse
880 Parts List 8-bolt heavy duty single speed
230/270/271/852 Install Guide Clutch Pack PTOs
277/278/859 Install Guide For Allison New World Transmissions

Muncie PTO

TG Parts List 6/8-bolt single speed
RL Parts List 6/8-bolt forward & reverse
83 Parts List 8-bolt forward & reverse




Hydraulic applications are quite common in mobile power and varies in it's use and circuitry. Here are a few references we hope you find helpful.

Permco Gemini Dual use pump/valve for end dump and live floor applications
Permco Gear Pump/Bearing Specs Flows and horsepower requirements by series
Permco Bushing Pump Specs Flows and horsepower requirements: 197, 257 Series
Permco Gear Motor Specs Flow, HP and RPM specifications