I'm interested in getting the opinions of dealer techs/professional
mechanics on the differences that I'm finding in the design of oil seals
among OEM and aftermarket sources. Specifically, the camshaft oil seal for
my 1987 VW GTI 8V. An aftermarket source sold me the camshaft seal for about
$5.00. It measures 47 mm OD x 32 mm ID x 10 mm and features a spring-loaded
seal lip with an embossed cross-hatch pattern where the seal contacts the
shaft. The entire seal was molded from a compliant black material on a
metallic backbone.

On a recent visit to my local VW dealer, I looked at the camshaft seal they
were selling for my car (P/N 038 103 085E). It measured 48 mm OD x 35 mm ID
x 10 mm and features a more rigid, non spring-loaded sealing lip. The
sealing lip also appeared to have been molded from a different compound than
the rest of the seal (brownish in color), and appeared to have been
particulate reinforced and/or infused with dry film lube. The pattern on the
sealing lip was a series of circumferential grooves instead of a cross-hatch
pattern. Price was about $8.00.

These differences seem fairly significant considering that the two parts are
specified for the exact same application. The seal sold by the dealer seems
to be a much more highly engineered design that perhaps solved some seal
longevity issues. And since the price is only slightly more, why risk the
aftermarket part?

My question to the dealer techs/professional mechanics is this: have you
guys noticed these differences in seal design? If so, have you noticed any
significant differences in seal performance between the seal designs?

Sorry about turning a relatively straight-forward oil seal replacement task
into a science project (not the first time for me), but this inquiring mind
would like to know.

Thanks,

--
Kent
1987 VW GTI 8V, original owner, 221,500+ miles

1. What brand was the aftermarket and also a part #

I have compared 2 aftermarket seals to VW seals and found them to be
EXCELLENT.

They were Timken and FelPro.

Have installed both brand cam seals on a variety of VW's with no
problems.

Paul
'89 Jetta

Printed on the face of the aftermarket seal is "DPH", "Germany", "32",
"47", "10", and "2". I just pulled the old seals out of my car today, and
they look just like the aftermarket seals. Since I'm the original owner of
the car and its only mechanic, I know that these seals were factory
installed.

--
Kent
1987 VW GTI 8V, original owner, 221,500+ miles

"Simplstupd" <simplstupd (AT) aol (DOT) com> wrote

All I can say I have seen newer seals which no longer have the spring in
them. Are they better than the old design... only time will tell. I can
tell you our newer VW's have less oil leaks caused by seals then the older
cars. I would think the dimensions should be the same on the old & new style
seals... so do a double check.

"Kent" <immortala2 (AT) yahoo (DOT) com> wrote

That's what caught my attention, the newer seals are 3 mm larger in ID (35
mm vs. 32 mm), and 1 mm larger in OD (48 mm vs. 47 mm). I've even had
everyone double check their part numbers, and I'm going to have them triple
check before I install the new seal.

My theory is that since the sealing lip of the new seal is noticeably more
rigid than the old seal and doesn't have a spring to expand for the sealing
force, the uninstalled ID doesn't need to be as large. I don't have a theory
for why the OD is 1 mm larger other than to allow the seal to fit more
tightly in the bore.

I think it's interesting to note the subtle engineering improvements that
are made to these detail parts as the years go by. Or maybe I just have too
much spare time on my hands...
--
Kent
1987 VW GTI 8V, original owner, 221,500+ miles

"Woodchuck" <stv_euroski (AT) yahoo (DOT) com> wrote