In a message dated 96-08-21 00:39:44 EDT, airhedrz@mailhost.iconn.net (Robert
Zirpolo) writes:
<< I've read the suggestions and comments from several contributors
concerning front end clunk and wheel problems but before I do anything rash
(like buying a new set of wheels and hubs) I need to know just how to
determine if the splines on the wheels or hubs are worn down enough to
warrant replacement. >>
Since many keep asking this question, I hereby post my response to the whole
list.
OK guys (and gals),
Check your splines soon, then decide what you need to replace and what you
don't. In case you missed it, here's how you do it.
When the splines are new, they have a small flat at the ridge and no
discernable clearance, slip on and off smoothly when clean, have little or no
backlash even with the knockoffs removed.
When the splines get warn some, the flat at the top dissappears, the ridge
comes to a sharp point, and the wheel developes a bit of rotational backlash,
maybe 1/4 inch at the tire tread with the hand brake on hard and the knock
off loose. Still driveable at this point but makes that nasty clunking
noise. If you're not buying new splines at this time, the best advice is to
keep the knockoffs really tight and don't stomp on the brakes hard.
When the splines are worn nearly to the point of failure, the splines get
shorter (height not length), have a very sharp ridge you can nearly cut your
finger on, have a lot of bachlash, like 1/2 inch or more at the tire tread
with the knockoff loose. When you remove the knockoff, the wheel may also
wobble a bit on the splined hub. At this point it's a death trap, one good
stab at the brakes and the splines wipe off to a rounded ridge, the wheel hub
rotates on the axel hub, and the wheel free wheels, might even loose the
knockoff when you try to drive off (UNDO does). This is not something you
want to happen on the road.
If left alone for a long time, and especially if the knockoffs are not tight
enough, the rear splines will wear more, being subject to constantly
reversing torque. Jack and block up the car, remove all four wheels, clean
and inspect the axel splines and the wheel splines, use a magnifying glass if
necessary. Compare the front and read axel splines, expect the rear ones to
be worn more, the front ones not much. The wheel hub splines could be all
about the same if the wheels were rotated occasionally.
Get someone to stand on the brake pedal while you try all four wheels on a
front spindle, say start on the left front. Leave the spinner off and check
the wheel for backlash. Try to rate each wheel in turn for the amount of
backlash, 1, 2, 3, 4 (and 5 if you try the spare also), 1 being the best with
the least and 5 being the worst with the most, and tag the wheels
accordingly. Then take the best wheel with the least backlash, test it at
all four corners, and rate the splined axel hubs the same way, from 1 to 4, 1
being the best with the least slop and 4 being the worst with the most slop.
Now for the scary part, put the number 4 (or 5) wheel on the number 4 axel,
and check the backlash. Compare that combination with the results of the #1
wheel on the #1 axel. Then get out the magnifying glass and take another
look at all the splines. By this time you should have a pretty good idea of
what "good" is and what "bad" is, and which splines you may have to replace.
Concerned,
Barney -- 1958 MGA
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