Truck Topics

The Tool Box - Greasing your Truck

Welcome back! We have begun the process of learning how to do some of our own maintenance.  This time, lubing (greasing) the chassis and drive line is in order.  This job will require a new tool for the box – A Grease Gun with a flexible hose. Coveralls and gloves (rubber disposable) are good for helping to keep you clean while crawling around under the truck. I was at Tractor Supply Co. the other day and saw a cordless electric grease gun for $99.00, a good price, or you can get a manual lever action gun for about $15.00.  

You will also need tubes of grease, available at parts stores everywhere; just ask for good chassis grease.  Since I do my own work I use synthetic grease, but you can use the grease of your own liking.  Each OEM sets it own lube requirements found in your owner’s manual.  I use 15,000 miles as a good lube mileage. The grease zerk is a small quick connect fitting that looks like a small volcano (no smoke) with a small ball at the top.

Every truck is different, but every truck I have been under in the last 25 years is about the same as far as chassis parts.  Some trucks have clutches and linkage some have automatic transmissions with no linkage.   Some have three axles, some two, some have a fifth wheel, others a lift gate, whatever equipment you have, most likely, if it moves it needs to be lubed.  

Grease guns are easy to use. Just push the end onto the zerk (it should snap on) & pump away.  Be sure to wipe the zerk clean before hooking up the gun.

For this job we will start at the left front wheel (driver’s side) under the hood.  At the front of the frame you will find the steering gear box, where the small shaft goes up to the steering wheel there may be a zerk on the slip tube. Check the u-joint at the top of the steering gear box for a zerk and, if equipped, just give one pump of the grease gun to each zerk.  The shaft coming out of the steering gear box (the largest shaft) there may be a zerk on the body of the box (some have this and some don’t); this needs only one pump of the gun.  Over-greasing the output shaft on the steering gear box could cause a power steering fluid leak.

From there, every rod end will have a zerk, hook up gun and pump until you get some clean grease coming out of the rubber boots around the rod ends.   The rod ends are at the ends of the linkage from the steering gear box to the left front wheel, and then from the left front wheel to the right front wheel. There are 3 rod ends on the left side and one the right side.  At the end of the steering axle there is a joint called the steering knuckle, with a zerk on the top and bottom of each knuckle.  Just above the knuckle is the s-cam tube and the slack adjuster, one zerk on each is normal.  The cam tube, slack adjuster and steering knuckle are on the right side also.  Some trucks have greaseable spring pins at the end of each leaf spring.  On each side there should be one zerk at the front and two zerks at the rear.  If yours doesn’t have these, don’t worry it’s just different suspension technology.  

This is all that can be lubed from above.  Now on your back and under the truck.  The front end is now done so we will work to the rear of the truck. The clutch (if equipped) should have a zerk on the bottom of the bell housing (between engine and transmission) one pump of grease gun is all this zerk needs.  The linkage may have one zerk on each side of the bell housing on the throw-out bearing pivot shaft, one pump each.  Moving on back, the first u-joint is at the back of the transmission.  Most driveline u-joints have two zerks, opposite of each other. You need only grease one as they fill the same cavity; just use zerk easiest to reach.  First hook up the gun and pump until grease comes out of bearing cups.  Move rearwards greasing all u-joints along the way.  There is a slip yoke at the next to last u-joint that needs greased, 15 – 20 shots is good. Each rear axle has a zerk on each slack adjuster and cam tube on each side.  

Liftable axles may have a zerk at the slack adjuster end and on the brake end.  You need to look for zerks for your own application.  If you have a straight truck with dolly legs they have zerks also five to ten shots each.  Some lift gates have greaseable joints – unfold it and look at every hinge point.  Tractors have fifth wheels, most of these have zerks to grease at the pivot points and zerks on the side that will grease the face.   That’s the sum of a lube job: about $50.00 at a shop, or $4.00 a tube for lithium grease, $8.00 a tube for synthetic grease,  one hour of your time, plus you get a bonus of looking around under your truck, checking for hoses chafing, or wires rubbing – stopping a future problem or a DOT out of service.  

One more thing while you are under the truck. Take an adjustable wrench and check the drive axle oil levels. The plug is about halfway up on the rear of the axle housing. Unscrew the plug to the left. Oil should be at the bottom of hole or some may run out. If it is low, fill it with the proper oil thru the same hole you just checked.  You can find what kind of oil you need from your owner’s manual. Reinstall plug turning to the right and tighten.

You can also look into the brakes, the pads should be no thinner than ¼” and no oil on the shoes. If the shoes are less than ¼” or are oily they need to be replaced as they are worn out or a wheel seal maybe leaking. To get brakes replaced or seal replaced you need to go to the shop for service work.  

Until next time, Grease UP!