How To: Tune-up Driveline - PartSource: Automotive, Truck Parts & Accessories

How To Tune-up Driveline

We've all been there. Driving down the highway when you hear the "clickity clack" underneath you. Proper driveline maintenance plays a key role in good vehicle performance. We're going to show you how to inspect, remove and replace everything from the Pinion Seal to the U-Joint.

Remember, if you have any questions or if you're unsure of anything, feel free to contact the Parts Pros at your local PartSource. They’are always ready to help, no matter what the job is.

Let’s go!

Make Safety Your Top Priority

Every vehicle is different. When it comes to maintenance and repairs, always follow the vehicle's owner's manual.

Safety should be your number one priority. Don't smoke, drink alcoholic beverages, or wear a necktie while working on the car. Watch out for hot objects, sharp instruments, hazardous materials and other potential safety hazards in and around your workspace.

Don't work with a Philips when the job calls for a flat. Substituting tools can compromise your safety or your vehicle's performance.

Finally, when the fun turns to frustration, or if the job requires specialized knowledge beyond your capabilities, please do not attempt it yourself. Talk to a Parts Pro or seek the assistance of a professional mechanic or installer. The last thing we want is someone getting hurt.

Before Getting Started

Raise & support the rear of the vehicle securely with jack stands. Make sure you block the front wheels so the vehicle won't roll forward off of the jack stands.

IMPORTANT - Always disconnect the negative battery cable before you begin any work on your vehicle.

See your local PartSource for free print outs from Mitchell On Demand for vehicle specific instructions, or to purchase a Haynes Manual.


Simple Driveline Inspection

Inspect the driveshaft for any dents or cracks. If you find them, the driveshaft must be replaced. Check for oil leakage at both the front & rear end of the driveshaft. If there is oil leaking where the driveshaft enters the transmission or transfer case, the transmission/transfer case seals need to be replaced. If there is oil leaking where the driveshaft enters the rear differential, the rear pinion seals need to be changed.
There are two ways to check the u-joints. If you have someone to help out, have them rotate the rear wheels so the driveshaft rotates, while you visually inspect the u-joints from under the vehicle to make sure they are working properly. Make sure there is no noise, binding, or any looseness in the joint. You can also check the u-joints without rotating the driveshaft. Place your hands on each side of the u-joint & twist it back and forth. Any movement at all means that you should replace the u-joint.
IMPORTANT - Make sure to check all driveshafts on 4WD models.
Inspect the center support hanger bearing by moving the driveshaft up & down while watching for movement. Also inspect the rubber for cracks, wear and tear. Differential Fluid Change

Driveshaft R&R

Rear Driveshaft Removal Make sure the transmission is in neutral and the parking brake is off. Ensure that the vehicle is properly raised and supported.
If the same driveshaft is to be reinstalled, mark the driveshaft and differential flange with a hammer and a punch. This will help ensure the driveshaft is reinstalled in the same position to maintain proper balance.
Remove the rear u-joint bolts and straps. If the bolts are not accessible, turn the driveshaft by rotating the rear wheels.
Tape the bearing caps of the u-joint.
Lower the rear end of the driveshaft.
Slide the front end of the driveshaft out of the transmission or transfer case. Wrap a plastic bag over the transmission or transfer case housing, and secure it with an elastic band. This will prevent any debris entering while the driveshaft is out.
Rear Driveshaft Installation Remove the plastic bag from the transmission case and inspect the oil and oil seal. Wipe the housing clean of all debris.
Slide the front end of the driveshaft into the transmission case.
Raise the rear of the driveshaft. If installing the same driveshaft, make sure the marks are aligned. You may need to rotate the rear wheels.
Remove the tap securing the u-joint bearing caps. Install straps and all bolts to specified torque.
Front Driveshaft Removal If present, remove skid plate.
Mark the driveshaft in relation to the front differential flange and the transfer case flange using a hammer and a punch.
Remove the straps and bolts from the differential flange and transfer case flange.
Push the rear of the driveshaft forward to separate it from the transfer case flange.
Lower the driveshaft to separate it from the differential flange.
Front Driveshaft Installation Raise and attach the front end of the driveshaft to the differential flange and tighten the straps and bolts (finger tight).
Raise the rear of the driveshaft into place and install the straps and bolts.
Tighten all bolts to specified torque.

Rear Pinion Seal R&R

Block the front wheels so that the vehicle cannot roll forward off of the jack stands.
Disconnect the rear of the driveshaft and secure it out of the way.
Mark the relative positions of the pinion shaft, companion flange and nut with a hammer and a punch.
Count the number of threads visible from the end of the nut to the end of the pinion shaft.
Write the number down. It will come in handy in the future.
Remove the pinion nut. Keep the companion flange from moving, while you are removing the pinion nut, a large crescent wrench can be used to hold the companion flange in place.
Using a 2 or 3 jaw puller remove the companion flange. Do not damage the flange by prying it.
Remove the old pinion seal by prying it out with a flat head screwdriver.
Apply a thin coat of high temperature grease to the new pinion seal.
Install the new pinion seal ensuring that it goes in squarely. Use a large socket to tap the seal into place.
Install the companion flange, making sure to line up the marks you made during disassembly. You may need to use the pinion nut to draw the flange into place
IMPORTANT - Never hammer on the flange. This will cause damage.
Install the pinion nut with the same number of threads that were visible before disassembly.
Connect the rear of the driveshaft.
See your local PartSource for free print outs from Mitchell On Demand for vehicle specific instructions, or to purchase a Haynes Manual.

U Joint Removal and Replacement

Outer Snap Ring Remove the driveshaft. ( See above) Be careful not to knock the bearing caps off the exposed ends of the u-joint.
Place the driveshaft on a work bench equipped with a vise.
Use duct tape or electrical tape to secure the bearing caps on any of the u-joints that are not being replaced.
If the vehicle is equipped with greaseable u-joints, mark the yoke in relation to the position of the grease fitting. You will need this for installation.
Remove the bearing caps from the ends of the u-joint not seated in the yoke.
Place the yoke of the driveshaft in the vise.
Remove the outer snap rings from both sides of the u-joint. You can use snap-ring pliers or needle-nose pliers.
Make sure the yoke of the driveshaft is positioned in the vise so you can use a ¾ inch socket on one of the bearing caps and hit the socket with a hammer.
Hammer on the ¾ inch socket until the bearing cap breaks through to the other side of the yoke.
Remove the other bearing cap with a set of pliers.
Remove the u-joint.
Align the new u-joint so that the grease fitting is in place with the mark you made earlier.
Remove the appropriate bearing caps being careful not to shift or loose any needle bearings.
Use duct tape or electrical tape to secure the other bearing caps.
Place a bearing cap at one end of the yoke and move the u-joint into the cap, making sure the needle bearings don't shift.
Place the yoke on a solid surface and tape on the bearing cap while holding the u-joint in place. You don’t have to seat the cap completely.
Place the other bearing cap at the other end of the yoke and move the u-joint into the cap making sure none of the needle bearings don't shift.
Place the yoke on a solid surface and tape the bearing cap while holding the u-joint in place. You don’t have to seat the cap completely.
Position a C Clamp on each bearing cap and tighten until the bearing caps are flush with the yoke.
Use a ¾ inch socket to seat the bearing caps in place. Install the outer snap rings. Do this to both sides.
Remove tape from the exposed bearing caps.
Install the driveshaft (see instructions for “Driveshaft Installation” above).
Tighten all bolts to the specified torque. CV Shaft R&R
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