Xk120 rear Spline Brake fitment

Rear brake drum does not seat all the way into the lip of the backing plate. Splines and drums new, rear axle professionally services all bolted up to proper torque. Splines are aftermarket and shoe wear shows this fitment has been a long term issue based upon wear. Has anyone heard that any of the aftermarket spline hubs have a fitment problem spacing the brake drum too far out? I invite suggestions


2HA DIFF ie 3.77 or
ok not an ENV is it?

Is this the original backing plate and drum, but a new hub?
Give us a picture of the hub.
Here’s an original.

My car has a 4HA Diff, currently with 3.33 I changed out the 3.54. I noticed the fitment issue and related brake wear showing that some of the shoe was outside the drum towards the inside and realized it must have been that way for years after I bought the new splined hubs. Is there a spacer I am unaware of after owning this car since 1973? Is it possible that the aftermarket splinned hud is not machined to create the proper spacing. They were purchased from Jason at XK’s Unlimited years ago. Appreciate your suggestions.

Did you convert this car from 5 lug bolt-on wheels?

There is a spacer say 1/4" thick some seem to have step on them others don’t but the mechanics of this is not my strong point

Just checking.
The rear drums should have a flat face.
The front drums should have a dished face.

Terry: I had rear gear and end float set by local Diff Shop. They did a great job on my Italian car. I had brake backing plates powder coated so they had to put them back on. Note location of the brake backing plate in relation to heavy metal retention ring!

Order of backing plate reversed on MK Vl and 120.

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Yep, that’s the problem, wrong assembly order.
Here is my axle from 681114. I can feel the bearing retainer plate in that gap, about 1/8" to 3/16" thick.
Shims on first, then bearing retainer plate, then brake backing plate, then oil seal retainer.

So nobody has said it yet but your metal retention ring is on the wrong side of the brake backing plate. The seal retainer and a paper gasket should be the only thing visible on the outside of the backing plate, as shown in Rob’s picture. Thus the backing plate is stepped inward the thickness of the gasket and the retaining ring.

Best regards,
Tom Brady

I would say tom is correct
The order for these should be in parts book

From the XK120 service manual.

So is this one of those instances where the Service Manual illustration is incorrect. Recycled from an earlier model that was different? I feel like I’ve seen this before. Deja vu all over again.

All of the bearing retainers I have have lines on them from the flat edge where they were bolted to the seal retainer. That matches the order shown in the manual. Item 43 on the left and item 44 on the right. The raised lip on 43 registers inside the brake backing plate (not shown) does it not?

That is the order shown in the factory service manual.

Hi Mike,
Interesting observations, the plot thickens. My XK-120 Spare Parts Catalogue, amended June 1954 and reprinted January, 1958 clearly shows the heavy ring located behind the brake backing plate, as does Viart in XK-120 Explored. That position makes more sense to me as the raised ring serves to locate the backing plate and centralize it. It also allows the brake shoes to fully contact the drum, the original problem being discussed in this thread.

It appears to me the manuals are all outdated, not the first time we have seen that, as you said.

On an XK150 with disc brakes this plate is left out and the caliper mounting plate goes in same spot

Be careful to follow the instructions for XK120 and NOT Mark VII which are on the same page, and be aware the illustration Plate H.1 and index on page H.7 is for Mark VII, NOT XK120.
And yes, the Mark VII instructions and illustration are recycled from Mark V which is the same basic 2HA as Mark VII.

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Not ALL 120’s had the “dished” front brake drums…
I believe ALL 120DHC’s left the factory with “Flat/Flat Drums”!
Charles Ch #677556.