Suspension grease fitting question.

[FatherAndSon]

All of the holes for the grease fittings in my upper control arms and the bushing sleeve assemblies have no threads. Are they supposed to since the grease fittings are threaded? The manual only says to install them in two places:

Page 23 - "Install the grease fitting in the lower control arm ball joint."
Page 31 - "Install the grease fitting into the pivot points on the upper control arm."

Also, I received 4 grease fittings for the lower suspension and 4 for the upper suspension. However, the lower suspension needed two in the lower control arms and in the 4 bushing sleeve assemblies so shouldn't there have been 6 for that?

Thanks,
Matthew

[egchewy79]

They should’ve been tapped. Buy a tap online and buy extra zerk fittings while you’re at it. It’s nice to have a90* option in some locations that would otherwise be difficult to access.

[Mastertech5]

In my 40+ years as a tech I found that most of the time the holes in a new part are not tapped. The grease fitting threads are tapered, so I would try to get it started by hand, put a closed end wrench on it and push down on it with a finger and turn the wrench. Don't try to get the hex all the way down if it doesn't seem like it wants to go, it might snap off. As long as it's good and snug.

[mikeinatlanta]

Do not tap. You need self tapping grease fittings, and most are. I say most because I don't know for sure if all are, but all of mine in my fitting kit are.

[mkassab]

I had the same situation. Factory Five said to just use the fitting to tap.... but I didn't like that. I did tap mine and it's a metric thread. Check my build site for more info.... link in signature.

Mark

[mikeinatlanta]

Using the fitting vs tap provides a closer tolerance fit, stronger deformed thread vs cut, and a bit of a built in self locking feature. Same as self tapping screws make a stronger more durable thread than a tap.

[Dgc333]

In my 40+ years as a tech I found that most of the time the holes in a new part are not tapped. The grease fitting threads are tapered, so I would try to get it started by hand, put a closed end wrench on it and push down on it with a finger and turn the wrench. Don't try to get the hex all the way down if it doesn't seem like it wants to go, it might snap off. As long as it's good and snug.

That has been my experience in my 50ish years of wrenching, parts are not tapped and I have never had an issue using the grease fitting to self tap.

My 33 Speedstar kit did not come with enough grease fittings to fill all the holes which was fine by me. All of the control arm pivots need a 90 degree fitting in order to get a grease gun on them.

[lance corsi]

This convo is a bit foreign to me. In my career of making parts for other people, I always tapped the grease fitting holes. Grease fittings come in a variety of thread sizes ranging from 1/4-28, 1/16 pipe thread and 1/8 pipe thread. I suppose there are a variety of other threads, but these three are the most common American thread sizes I’ve used. I’ve never heard of self-tapping zerk fittings but apparently they do exist. I wouldn’t want to try it on the larger sizes.

[DonImbimbo]

On my 35 truck the upper and lower suspension parts were not threaded. I don't know if the supplied zerks are Metric or SAE because I did not use them. I tapped with 1/4-28 and used my own 45 & 90 degree fittings.