Gearvendors OD no reverse

[1995voyagerES]

Some day it popped "out of gear" because of an assh*** who was going to hit me so I had to floor it, brake hard and floor it again and that was the moment where it "popped out". I had no forward gear at that time...had to stop...switched the OD off, restarted the engine and then I could drive again - even OD worked fine the rest on my way to work.

As I mentioned in my first post...
Could this info point more to "whats going on" ?

Thanks to everyone for your time to help me with this problem !!!

 

[hce]

As I mentioned in my first post...
Could this info point more to "whats going on" ?

On the surface I did not think the GV would cause the problem, but the more I read and associated it with rebuilding a GV a few years ago the more it points to the GV.

 

[Black dawg]

How is your GV wired and controlled. I have mine with just a switch, and if I forget to turn it off, I have no reverse.

 

[1995voyagerES]

It has a controller box and a switch where I can switch between MAN/AUTO.
The complete system gets power from a switch in my headconsole - I can shut it off completely.

And yes, I already tried to disconnect the solenoid on the GV ;-)

 

[jim x 3]

Proposed mechanism of failure

OBs and OP:

I don't have an overdrive system such as this, just a 5Sp ZF, so take this post with a grain of salt. I was interested in how the GV unit functions, so I took a look at:

http://www.uniquecarsandparts.com.au/how_it_works_laycock_overdrive.htm
this shows some nice diagrams of how the gear vendors work

If the GV unit works as such in the OPs truck, then let me propose the following failure mode that might reflect the symptoms he has.

- The cone clutch properly engages the case, so the GV unit works properly on OD.
- The cone clutch fails to engage the annulus, so the GV unit slips in direct, except that the overrunning clutch functions to transmit power from GV input to output driving forward, so the unit appears to function correctly. But in reverse the overrunning clutch causes the GV output shaft to freewheel. So no reverse.

Does that make any sense?

Regards,

 

[1995voyagerES]

Update

I pulled the OD unit today and opened it up and TADA the cone clutch is gone (no friction material left). Other than that everything else looks fine.
What I noticed: If I spin the overrunning clutch with my fingers only in one direction it's turning the output shaft - is that normal?

 

[hce]

Update

I pulled the OD unit today and opened it up and TADA the cone clutch is gone (no friction material left). Other than that everything else looks fine.
What I noticed: If I spin the overrunning clutch with my fingers only in one direction it's turning the output shaft - is that normal?

That's what an overrunning clutch does, transmits power in one direction and freewheels in the other.

 

[1995voyagerES]

Ok, I see.

So the only problem would be the cone clutch ... that would be to easy

Is there a good source where I can get a new one?
(other than maximum-overdrive)

 

[hce]

Since your are in germany I would start searching the web for laycock overdrive parts.
found this no clutch listed but I would give them a call and ask.

 

[jaluhn83]

I strongly recommend you check the t-case while you're at it. The random popping out of gear is same symptom I had with mine for a few months until it finally hit permanent neutral on me going down the freeway - not a fun adventure. The oil pump in mine spun and the hi/lo shift fork was worn so that it no longer held the shift collar in gear. Sounds very similar to what you have.

 

[jaluhn83]

The US Gear over under trans fails and your stuck where it happens.

Only if you totally destroy the gears or shift teeth... would take some doing to manage to total one badly enough you're totally stuck.

 

[1995voyagerES]

Since your are in germany I would start searching the web for laycock overdrive parts.
found this no clutch listed but I would give them a call and ask.

Thanks !!!
I mailed them. I hope I hear good things back.

I'll keep you updated.

 

[1995voyagerES]

No, they won't sell me parts either
Next: maximum overdrive

 

[Bart F-350]

No, they won't sell me parts either
Next: maximum overdrive

Why? because it's no Volvo???

 

[Bart F-350]

BTW, these GKN, I thought they were British? I just saw they are California based?
Is that the same product as a GV?
or are they only selling parts?