Sign in to follow this  

Recommended Posts

AnaRamona    5

Hi,

my transmission in my 1969 Riviera goes reverse and in first gear. 

It sometimes shifts to second if I step on the gas hard, and is often shifting  back to first when not necessary. There is no third. It's not missing fluid. Could anyone please make some suggestions of what it might be?

Thank you.

Share this post


Link to post
Share on other sites
1965rivgs    54
2 hours ago, AnaRamona said:

Hi,

my transmission in my 1969 Riviera goes reverse and in first gear. 

It sometimes shifts to second if I step on the gas hard, and is often shifting  back to first when not necessary. There is no third. It's not missing fluid. Could anyone please make some suggestions of what it might be?

Thank you.

Modulator or its vacuum source

  Tom

  • Like 2

Share this post


Link to post
Share on other sites
AnaRamona    5
On 9/9/2017 at 1:11 PM, 1965rivgs said:

Modulator or its vacuum source

  Tom

 

On 9/11/2017 at 3:50 AM, Mr Riviera said:

Check the line that goes down to the modulator  to see if it is plugged up as well  .

I have changed the vacuum modulator, and everything is plugged in. The liquid level is ok. Reverse works fine. When I put it in drive, it acts as if it's between gears, I have to step on the gas multiple times to get it going. I don't know what else to do.

Share this post


Link to post
Share on other sites
RivNut    1,013

The vacuum modulator holds upshifts.  Sounds like it's time to visit your local transmission shop.  Just make sure the shop has someone old enough to have worked on TH400's 

  • Like 1

Share this post


Link to post
Share on other sites
1965rivgs    54
12 hours ago, AnaRamona said:

 

I have changed the vacuum modulator, and everything is plugged in. The liquid level is ok. Reverse works fine. When I put it in drive, it acts as if it's between gears, I have to step on the gas multiple times to get it going. I don't know what else to do.

Your symptoms now are different than your first post? Probably a good time to take the car to someone who is able to evaluate the symptoms like a trans shop. For what it`s worth, sounds like the pump,

  Tom

  • Like 1

Share this post


Link to post
Share on other sites
KongaMan    170

Concur with the pump possibly being at fault.  When my pump went out, it was like being in neutral until it eventually caught.  Right up until the point it failed completely. ;)

  • Like 1

Share this post


Link to post
Share on other sites
AnaRamona    5
7 hours ago, 1965rivgs said:

Your symptoms now are different than your first post? Probably a good time to take the car to someone who is able to evaluate the symptoms like a trans shop. For what it`s worth, sounds like the pump,

  Tom

Yeah, it seems it's getting worse.

I'll order a new pump.

Finding a good mechanic that knows around american classics over here is no easy job.

Thank you for the reply

Share this post


Link to post
Share on other sites
jsgun    31

Yep, it'll still work. What happens is that the pump can still pump a volume of oil, but at a lower pressure. It's losing pressure because an internal seal most likely failed, and the pressurized oil is spraying out of those seal areas, instead of being directed out the pump and reaching the control valves. The way the pumps are designed, they never really fail completely, they'll keep pumping. It's the seals that give out. That's why it would engage when you floored it.... it was generating enough pressure at high RPM to switch the valves and engage bands.

 

For what it's worth, they're not that difficult to rebuild. My brother rebuilt his 64 Rambler's transmission (a Ford FMX of all things) in our driveway. You just have to be absolutely religious about keeping the internals clean, and making absolutely positive that you follow instructions. He laid his clutch packs out on a piece of plywood, and made sure to keep everything in order. I believe he did it in a half day, and that was taking his time.

  • Like 1

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this