Shimano SPD pedals set the benchmark in terms of longevity, consistency, and ubiquity. Fortunately, they are very easy to service as well, so you’ll be able to get years and years of trouble-free use from your pedals.
Let’s walk through the process of servicing your Shimano SPD clipless pedals. First thing you’ll want to do is place the pedal in a vice with soft jaws and secure it. If you don’t have soft jaws, you can use an 8mm allen by securing it in the vice and resting the pedal on the end of the allen. Now we can loosen the pedal body from the axle. To remove the pedal body, various tools are necessary depending on which generation your pedal is. Newer pedals, like this XT all mountain pedal, require a 17mm cone wrench to hold the lock bolt while turning the pedal to break it free. Keep in mind that the right side pedal is left-hand, or reverse-threaded.
Once the pedal body is loose from the axle you can pull it off and clean it out. Before adjusting the bearings on the axle, clean off all the old grease so you have a clean surface to work on. Adjusting the axle bearings is done with a 7mm and 10mm open wrench. You can also use a 7mm socket if you don’t have a 7mm open wrench. To adjust the bearings, loosen the lock nut with the 7mm wrench or socket, and then adjust the bearings with the 10mm wrench. Making this adjustment is almost exactly like adjusting a cup and cone style hub. Tighten down the nut with the 10mm wrench until there is no play in the axle, however often times it doesn’t take much more than being finger tight to remove the play.
Once you have the proper adjustment on the bearings you’ll tighten down the lock nut with the 7mm wrench. If after tightening the lock nut the axle feels too stiff, break it free again and then use the 10mm wrench to back the adjusting nut off the bearings and tighten to the lock nut. The last thing you’ll need to do is put the body back on the axle. Before doing this you’ll need to put a small amount of grease in the body. Shimano recommends their Special/Dura Ace grease that is also found in their hubs, but there is some flexibility here. If you live in a wet area, a waterproof grease may be a good idea. I like Dumonde Tech’s MR grease because, while it is waterproof, it isn’t as thick as some other waterproof greases, and can be thinned even further with a few drops of Dumonde Tech liquid grease if you feel it’s necessary. The body only needs a small amount of grease, and a little on the end of the axle is good as well.
All that’s left now is to put the body back on the axle. Slide the body back on the axle and tighten it down. Again, pay attention to which pedal you are working on and make sure you are turning it the correct way to tighten it. That’s all there is to it. Luckily, this process is similar for any SPD, or even SPD-SL pedal. The tools to remove the axle may vary slightly but the adjustment process is essentially the same for them all.