Pete & Aprille Chadwell wrote:
> Hi, gang!
>
> I just drove the TR6 a total of 393 miles over the Cascade mountains from
> Bend (my home) to Salem, Dayton (to visit BPNW!!) to Portland, and back to
> Bend. (Oregon, that is!) The trip went fine and although I did bring a
> supply of tools, I never had to use them!
>
> I did have a weird thing happen in Salem, however, after coming down off of
> a VERY enjoyable drive over the Santiam Pass on Highway 22. I think it was
> the first traffic light I came to... as I approached the light I took it
> out of gear and braked to stop for the light, my usual routine. As much as
> a FULL SECOND after coming to a COMPLETE STOP, I heard (and felt) several
> fairly heavy CLUNK sounds coming from the rear of the car. My first
> impression was that it came from the diff, but I'm not sure. Understand,
> these "clunks" came when the car was COMPLETELY STOPPED, gearbox in
> nuetral, foot on brake pedal, engine at idle.
>
> Now, the diff in this car has NEVER been rebuilt. I've had it out of the
> car a couple of times in the thirteen years I've owned the car, and I did
> replace (about 10 years ago) the diff mounting bushings. The UJ's are all
> fairly new and have maybe as much as 15000 miles on them.
>
> I've always fought the "clunks" from the rear of this car, doing everything
> SHORT of rebuilding the diff, all of which helped but the clunks were never
> TOTALLY gone. The diff, I think, suffers now from a whole HELL of a lot of
> play I think between the pinion and ring gear. I don't know much about
> diffs, but I know that shifting in my car is always tricky as I try to do
> it gently and smoothly to try to avoid getting a little "clunk" from the
> rear.
>
> There is no typical "gear noise" or "howling" that comes from the diff,
> though, at least not that I can hear. It is pretty quiet once you're
> finished shifting gears.
>
> Does anyone have any guesses as to what these clunks may have been? I was
> pretty worried (and puzzled) at the time and was afraid that the diff might
> finally expire along the way. As it turned out, it did this a couple more
> times driving through Salem, but once I got out on the open road again it
> was fine and it never acted up again. I arrived home safely last evening
> with no break-downs.
>
> This diff may have somewhere between 150,000 and 200,000 miles on it, so I
> KNOW it's gotta be AWFULLY tired. Any hunches out there as to how many
> more miles I might get out of it before it finally "lunches" given the
> condition it's in?
>
> Thanks in advance!
>
> Pete Chadwell
> 1973 TR6
> (and a differential with 3 feet in the grave and one on a banana peel!!)
Pete,
Were you doing a lot of engine braking going down the hill? You said you had
had the
diff mounting bushes replaced, but did you make any repairs/reinforcements to
the
frame/mounting bolts? It is very common for the right front mouting bolt to
tear out
of the crossmember/spring perch. Might it be possible that under prolonged
engine
braking that the loose bolt was forced up through the cracked area of the
crossmember
and when you stopped, normal vibration and gravity took over and the diff and
mounting
bolt dropped back down through the crossmember making the sound you heard? It
certainly would be worth a look (feel is more like it as you really can't see
much up
under there) to see if the mounting bolts are intact.
As someone else mentioned already, since you weren't moving at the time, I
can't see
how the diff itself would be making noises unless the wheels were turning.
Good luck!
Regards,
Brian Schlorff '61 TR-4 '64 TR-4 '72 TR-6 '79 Spit
---------------------------------------------------------------------
Power British Check out Power British
371 E. Main St. on the 'net!
Norristown, PA 19401
(610) 270-0505 http://www.powerbritish.com/~britcars
---------------------------------------------------------------------
|