Grease Zerks on the IRS

I removed the IRS from my XJS to replace the rear brake discs, pads & calipers. I did remove the two at the bottom. but one is broken.

Does anyone know what thread is on these little guys?

I would guess at 1/4x28. Again, just a guess.

I’ll be down to my garage in a little while and can check the size & thread on the one I removed and is still on the worktable.

That is correct: 1/4-28.

Thanks for the info. The bolts are metric, so I assumed the zerks were metric too.

What year XJS?

What bolts are metric? Metric size heads or you verifed metric size and thread pitch for the bolts?

Some Imperial/SAE (inch) sizes are very close to metric.

In working on my 83 XJS IRS mounts, I found that a 14 mm actually fit tighter to the 9/16" wrench nuts on the 3/8" bolts.

To make sure to avoid stripping the nuts with my 9/16 wrench, I used my 14 mm (which fit like a SnapOn wrench fits … scrap the paint off the bolt to fit the wrench on … SnapOn wrenches are above my budget).


Got a NAPA store near by? Take the good one there and match it. Maybe buy a spare, just in case!!!



This is a 1992 XJS, face lift.

I was referring to the bolt heads, not the threads. I did find my broken grease zerk was 1/4" 28 fine thread.

For the Zerk grease fittings?

I think the wrench size was 3/8, but I’d have to check to verify.

The wrench size is 3/8".

Thanks for the reply.

What MY is your Jag? There have posts about this topic (inc. inquiries from me), as to the location of those fittings and the #. The factory workshop literature has some pics that (vaguely) show the location of some of them. :frowning_face: IIRC, the total # was around 8 (even #, since they are in pairs on each side). ? :confused: IIRC, on some of them they are covered by a rubber “blanking” plug, which has to be removed to access them. There are zerks for the inner and outer wheel bearings, as well as for each of the u-joints back there. :thinking:

I think I saw on Ebay somewhere a large “multipack” of the zerks, in all kinds of different sizes … The price wasn’t bad, either … :+1: This was back when I was looking at replacing them as part of a rear lube job on Superblue (the guy at N.T.B. tried to “shoot” a couple of the ones on her back then for me w. his grease gun and, sadly, reported they were plogged up … :open_mouth: )

Again, if you have a local NAPA store nearby you should be able to match ALL Zerks on the car. No need to buy a multi-pack containing un-needed Zerks! Other Box Parts Stores also mostly carry multi-packs! NAPA prices are very, very cost effective. Just a satisfied patron for many years in many locations!

Same with O’Reilly’s and the others.

The closest NAPA is not that close to me. That said, at least when we were in Ormond Beach, the NAPA store in Daytona Beach far and away kept the most stock on the most things, making the extra 20-25 minute drive time useful at times.


I there still a NAPA Auto Parts Store at 821 N. US Hwy 1 in Ormond Beach? 386-366-9303 was their number.



Dick, that NAPA store closed many years ago. I remember it being there. I don’t recall if they closed that store or relocated it to another location not in Ormond Beach.

The closest NAPA store I went to was on ISB just east of Nova Rd.

I’m not sure if that NAPA store was there before, or if that may have been the new location for the other store.

Their people were very knowledgeable and their stock was quite extensive (compared to the ‘typical’ auto parts store).

We lived in The Trails, if you are familiar with Ormond Beach, and there was an AutoZone 5-7 minutes from our house and carried much of what I typically needed, while that NAPA store was 25 minutes away.

Convenience is also a big factor.

Here, where we live near Asheville (20 minutes to downtown Asheville in one direction and 15 minutes to downtown Hendersonville in the other direction) O’Reilly’s is 5-7 minutes away and has knowledgeable people, with an almost useless Discount 7-8 minutes away (‘useless’ because the few times I went it seemed like the people had just been hired … but I guess you need to learn somewhere).

The closest AuotZone is probably 15 minutes away, Advance is near them, with NAPA being a little past both, as I recall.

There, I think I’ve covered all “the usuals”, so equal mention to all. :slightly_smiling_face: