c3 transmission question

> I have had the xmission oil changed twice, last one about8-10 years


Boy Scouts of America,

I seems pretty obvious that you need to change the transmission fluid.
It's probably evaporated some and gumming up and something is sticking.

Ed

spud wrote:
>> I have had the xmission oil changed twice, last one about8-10 years
>
>
> Boy Scouts of America,
>
> I seems pretty obvious that you need to change the transmission fluid.
> It's probably evaporated some and gumming up and something is sticking.
>
> Ed
>
>

Good first step that's worked for me.

Use the correct fluid (important in an older
transmission to get the correct amount of
abrasive additive).

Change the filter.

--
pj

On Apr 12, 9:17*pm, pj > wrote:
> spud wrote:
> >> I have had the xmission oil changed twice, last one about8-10 years
>
> > Boy Scouts of America,
>
> > I seems pretty obvious that you need to change the transmission fluid.
> > It's probably evaporated some and gumming up and something is sticking.
>
> > Ed
>
> Good first step that's worked for me.
>
> Use the correct fluid (important in an older
> transmission to get the correct amount of
> abrasive additive).
>
> Change the filter.
>
> --
> pj

Do you think it would benefit from adding something into it as someone
else suggested BEFORE I change the fluid and filter - maybe run it for
a few hundred klicks or so first?

Today it is about 45 F or so and sunny and there is no problem with it
at all.

Do you think it would benefit from adding something into it as someone
else suggested BEFORE I change the fluid and filter - maybe run it for
a few hundred klicks or so first?




I agree with PDDeen. Those fix-its in a can can also do damage. Have the
fluid changed by a good transmisson shop and make sure they drain the torque
converter.

Spud

On Apr 13, 6:20*pm, "spud" > wrote:
> Do you think it would benefit from adding something into it as someone
> else suggested BEFORE I change the fluid and filter - maybe run it for
> a few hundred klicks or so first?
>
> I agree with PDDeen. * Those fix-its in a can can also do damage. * Have the
> fluid changed by a good transmisson shop and make sure they drain the torque
> converter.
>
> Spud

OK - How does one ensure they drain the torque converter? Is this the
sort of thing one can do at home? I may have mentioned I have a lot of
t hings I have to do to the beast anyway - like brake caliper
rebuilds, new composite rear spring, shocks, etc, and I think maybe a
new rad support.

> wrote in message
...
On Apr 13, 6:20 pm, "spud" > wrote:
> Do you think it would benefit from adding something into it as
> someone
> else suggested BEFORE I change the fluid and filter - maybe run it
> for
> a few hundred klicks or so first?
>
> I agree with PDDeen. Those fix-its in a can can also do damage. Have
> the
> fluid changed by a good transmisson shop and make sure they drain
> the torque
> converter.
>
> Spud

#OK - How does one ensure they drain the torque converter? Is this the
#sort of thing one can do at home? I may have mentioned I have a lot
of
#things I have to do to the beast anyway - like brake caliper
#rebuilds, new composite rear spring, shocks, etc, and I think maybe a
#new rad support.

Three ways to drain a converter, take it out and pour out the fluid or
drill a hole in it and then plug it before you refill. Most of the
time you can unhook the return line while running and let it pump new
fluid through the system until you get no more old fluid. Not an easy
task but it works, but in most cases not necessary.

On Apr 14, 1:37*pm, "Dad" > wrote:
> > wrote in message
>
> ...
> On Apr 13, 6:20 pm, "spud" > wrote:
>
> > Do you think it would benefit from adding something into it as
> > someone
> > else suggested BEFORE I change the fluid and filter - maybe run it
> > for
> > a few hundred klicks or so first?
>
> > I agree with PDDeen. Those fix-its in a can can also do damage. Have
> > the
> > fluid changed by a good transmisson shop and make sure they drain
> > the torque
> > converter.
>
> > Spud
>
> #OK - How does one ensure they drain the torque converter? Is this the
> #sort of thing one can do at home? I may have mentioned I have a lot
> of
> #things I have to do to the beast anyway - like brake caliper
> #rebuilds, new composite rear spring, shocks, etc, and I think maybe a
> #new rad support.
>
> Three ways to drain a converter, take it out and pour out the fluid or
> drill a hole in it and then plug it before you refill. Most of the
> time you can unhook the return line while running and let it pump new
> fluid through the system until you get no more old fluid. Not an easy
> task but it works, but in most cases not necessary.

I am ordering the bits and pieces I require, but how do I determine if
I have a THM 350 or THM 400 to make sure I get the right parts? A 1976
automatic with L-48 engine.

Thx & regards.

> wrote in message
...
On Apr 14, 1:37 pm, "Dad" > wrote:
> > wrote in message
>
> ...
> On Apr 13, 6:20 pm, "spud" > wrote:
>
> > Do you think it would benefit from adding something into it as
> > someone
> > else suggested BEFORE I change the fluid and filter - maybe run it
> > for
> > a few hundred klicks or so first?
>
> > I agree with PDDeen. Those fix-its in a can can also do damage.
> > Have
> > the
> > fluid changed by a good transmisson shop and make sure they drain
> > the torque
> > converter.
>
> > Spud
>
> #OK - How does one ensure they drain the torque converter? Is this
> the
> #sort of thing one can do at home? I may have mentioned I have a lot
> of
> #things I have to do to the beast anyway - like brake caliper
> #rebuilds, new composite rear spring, shocks, etc, and I think maybe
> a
> #new rad support.
>
> Three ways to drain a converter, take it out and pour out the fluid
> or
> drill a hole in it and then plug it before you refill. Most of the
> time you can unhook the return line while running and let it pump
> new
> fluid through the system until you get no more old fluid. Not an
> easy
> task but it works, but in most cases not necessary.

I am ordering the bits and pieces I require, but how do I determine if
I have a THM 350 or THM 400 to make sure I get the right parts? A 1976
automatic with L-48 engine.

Thx & regards.

Pan shape, 350 has one angle cut to keep it from having 90 degree
corners, the 400 has 3 of the corners not square and is bigger.

> wrote in message
...
On Apr 12, 9:17 pm, pj > wrote:
> spud wrote:
> >> I have had the xmission oil changed twice, last one about8-10 years
>
> > Boy Scouts of America,
>
> > I seems pretty obvious that you need to change the transmission fluid.
> > It's probably evaporated some and gumming up and something is sticking.
>
> > Ed
>
> Good first step that's worked for me.
>
> Use the correct fluid (important in an older
> transmission to get the correct amount of
> abrasive additive).
>
> Change the filter.
>
> --
> pj

Do you think it would benefit from adding something into it as someone
else suggested BEFORE I change the fluid and filter - maybe run it for
a few hundred klicks or so first?

Today it is about 45 F or so and sunny and there is no problem with it
at all.


________________

The Vette is laregely a "fair weather motorcar" ................... but I
agree will all of the above.

-W '68 roadster

On Apr 15, 2:12*pm, "Dad" > wrote:
> > wrote in message
>
> ...
> On Apr 14, 1:37 pm, "Dad" > wrote:
>
>
>
> > > wrote in message
>
> ....
> > On Apr 13, 6:20 pm, "spud" > wrote:
>
> > > Do you think it would benefit from adding something into it as
> > > someone
> > > else suggested BEFORE I change the fluid and filter - maybe run it
> > > for
> > > a few hundred klicks or so first?
>
> > > I agree with PDDeen. Those fix-its in a can can also do damage.
> > > Have
> > > the
> > > fluid changed by a good transmisson shop and make sure they drain
> > > the torque
> > > converter.
>
> > > Spud
>
> > #OK - How does one ensure they drain the torque converter? Is this
> > the
> > #sort of thing one can do at home? I may have mentioned I have a lot
> > of
> > #things I have to do to the beast anyway - like brake caliper
> > #rebuilds, new composite rear spring, shocks, etc, and I think maybe
> > a
> > #new rad support.
>
> > Three ways to drain a converter, take it out and pour out the fluid
> > or
> > drill a hole in it and then plug it before you refill. Most of the
> > time you can unhook the return line while running and let it pump
> > new
> > fluid through the system until you get no more old fluid. Not an
> > easy
> > task but it works, but in most cases not necessary.
>
> I am ordering the bits and pieces I require, but how do I determine if
> I have a THM 350 or THM 400 to make sure I get the right parts? A 1976
> automatic with L-48 engine.
>
> Thx & regards.
>
> Pan shape, 350 has one angle cut to keep it from having 90 degree
> corners, the 400 has 3 of the corners not square and is bigger.

Yes - thanks I checked and mine appears to be a TH350 from what I see
of the pan shape. As an aside I called the dealership and they wanted
$240 + tax to change the transmission fluid. I asked them what they
did for that (I thought maybe some special machine flush) but that was
just to drain the fluid and replace filter and gasket. They told me
$80 for the filter. I checked with corvette central and a filter and
gasket is $12.95 I think. Am I misunderstanding something? I can see
it is a bit of a messy job, but ......