1984 GMC C1500

Hi hazelaar. Welcome to the forum. The lube points are shown in the service manual, possibly in the owner's manual, and there are books just for this purpose, but they only show your vehicle as it came from the factory. Some replacement steering and suspension parts do not have grease fittings so you'll be looking all day for some that no longer exist, and some original parts did not have fittings while replacement parts do. (That is much more common on Fords). Going according to books and diagrams will let you overlook some fittings that might be on your truck now.

I can describe where to look for grease fittings for you but this assumes you know what the parts are. Start with the upper ball joints. Depending on the style, the fittings will be on top, (reach over the tops of the front tires and feel for them), or through an opening in the front or rear of the control arm adjacent to the ball joint. The lower ball joints' fittings hang straight down. On later models, they screwed into the sides of the control arms next to the ball joints. Newer models don't have these fittings. You will have four tie rod ends, two inners and two outers, each with a fitting. They are attached to the center link which is supported by the pitman arm on the steering gear box on one end and the idler arm on the other end. Look on both ends of that center link and look for a fitting on the idler arm pivot near the vehicle's frame. Two designs of idler arm were used but only one has a fitting on the pivot.

That takes care of the fittings commonly found on most full size trucks, other than Fords. In addition, on yours, look at the two lower control arms. You should see fittings for the four bushings, two pointing forward for the front bushings and two pointing rearward for the rear bushings. You won't find these on other brands and models. Also look for these four fittings on the upper control arm bushings. I think they were no longer used by 1984, but check to be sure. Finally, look at the universal joints on the drive shaft. The original ones most likely did not have fittings but replacements usually do. They could be between two of the bearing caps or screwed into one of the caps. If they're between two caps, you will have to rotate the shaft to pivot the joint to a place where it will allow the end of the grease gun hose to be pushed onto the fitting, or you'll need a needle point adapter. Some u-joints used a needle point fitting between two bearing caps. They look a lot different than standard grease fittings.

Caradiodoc