Ford C6 trans…..no reverse

[clementine]

Hello FABO,

Apologies for bringing in a non mopar item into the mix, but i am stumped.

Ive installed trans twice now and i am not an automatic guy. The guy who went through it is a Chrysler trans guy who also seems stumped to what is going on.

I have forward gears but no reverse.

Any ideas?

1970 ford truck C6/429 automatic.

New clutches and kit installed. Vacume to cannister thing and lines hooked up.

TIA

 

[HankRearden]

It's been almost thirty years since I've been into a c4 or c6 but I recall them being a clone of a torqueflite.
You should be able to air check the servo fie the reverse band. Make sure the seal wasn't damaged upon install.

 

[RustyRatRod]

Found this on the Ford truck forum I am a member of.

On a C6 for reverse to occur, there are 2 clutches that need to apply. First is the Reverse/high clutch (also called the direct clutch) and secondly is the Reverse/low clutch.

You mentioned you had forward speeds. You can do a bit of diagnostic testing to see which clutch(es) are not engaging by driving the car.

I'll assume you have the later '67 trans with "Select Shift" or the 'PRND21' gear selector and not the "green dot" drive "Dual Range" earlier '67 trans.

To test the Reverse/high clutch, put the trans in 'D' and verify that the trans does indeed go into 3rd as your accelerate up to appropriate speed. Count the shifts if you have to as 3rd gear uses that Reverse/high clutch.

To test the Reverse/low clutch, while moving forward put the gear selector in '2' or '1' (depending on your speed) and verify you have engine braking and it's not just overrunning (seemingly in neutral when you release the accelerator).

Results check:

If you have no 3rd in 'D', some items it could be:

* Bad seals(rubber) or worn frictions in the Reverse/high clutch,
* Broken seal rings(metal) on stator support
* Stuck check ball in the stator support
* Bad seals on the intermediate servo piston (accessible from outer side of case)
* Improperly torqued valve body or faulty valve body gasket

If you have no engine braking in either '2' or '1'

* Bad seals(rubber) or worn frictions in the Reverse/low clutch
* Improperly torqued valve body or faulty valve body gasket

 

[clementine]

Found this on the Ford truck forum I am a member of.

On a C6 for reverse to occur, there are 2 clutches that need to apply. First is the Reverse/high clutch (also called the direct clutch) and secondly is the Reverse/low clutch.

You mentioned you had forward speeds. You can do a bit of diagnostic testing to see which clutch(es) are not engaging by driving the car.

I'll assume you have the later '67 trans with "Select Shift" or the 'PRND21' gear selector and not the "green dot" drive "Dual Range" earlier '67 trans.

To test the Reverse/high clutch, put the trans in 'D' and verify that the trans does indeed go into 3rd as your accelerate up to appropriate speed. Count the shifts if you have to as 3rd gear uses that Reverse/high clutch.

To test the Reverse/low clutch, while moving forward put the gear selector in '2' or '1' (depending on your speed) and verify you have engine braking and it's not just overrunning (seemingly in neutral when you release the accelerator).

Results check:

If you have no 3rd in 'D', some items it could be:

* Bad seals(rubber) or worn frictions in the Reverse/high clutch,
* Broken seal rings(metal) on stator support
* Stuck check ball in the stator support
* Bad seals on the intermediate servo piston (accessible from outer side of case)
* Improperly torqued valve body or faulty valve body gasket

If you have no engine braking in either '2' or '1'

* Bad seals(rubber) or worn frictions in the Reverse/low clutch
* Improperly torqued valve body or faulty valve body gasket

I will perform this test. Will report back.

Thank you.

 

[clementine]

One of the challenges is getting the damn thing out of the shop and down the drive (perpendicular to drive) with no reverse. But I’ll try to do it on jack stands.

 

[ProjectBazza]

Found this on the Ford truck forum I am a member of.

FTE Forum?

 

[clementine]

@RustyRatRod

At this point (moving at snails pace here) when in drive there is no high gear. 1….2….. that’s it. Ill take off the shift linkage (i did this last time as well) and verify what i think i already know, the trans is PRND21 and is hitting all the positions.

I did not perform the downshifting test as no high gear is obtainable at this point.

 

[ProjectBazza]

@RustyRatRod

At this point (moving at snails pace here) when in drive there is no high gear. 1….2….. that’s it. Ill take off the shift linkage (i did this last time as well) and verify what i think i already know, the trans is PRND21 and is hitting all the positions.

I did not perform the downshifting test as no high gear is obtainable at this point.

Is this '70 "bumpside" your truck? If so:

Anyway, I was waiting for RRR to respond, but if he's AWOL, go to the FTE Forum (link below), create an account (free), and then either post in the appropriate forum, or do a search for member "Mark Kovalsky". He's an ex-Ford transmission engineer, and he's "wicked smart" on these type of questions.

Just note that that site moves much slower than this one, and it may take a while for him (or others) to respond.

Ford Truck Enthusiasts Forums - Ford truck and SUV owners and enthusiasts Community And Information Source.

The top community for Ford truck, F150, Super Duty, and SUVs owners and enthusiasts

www.ford-trucks.com

 

[RustyRatRod]

Is this '70 "bumpside" your truck? If so:

Anyway, I was waiting for RRR to respond, but if he's AWOL, go to the FTE Forum (link below), create an account (free), and then either post in the appropriate forum, or do a search for member "Mark Kovalsky". He's an ex-Ford transmission engineer, and he's "wicked smart" on these type of questions.

Just note that that site moves much slower than this one, and it may take a while for him (or others) to respond.

Ford Truck Enthusiasts Forums - Ford truck and SUV owners and enthusiasts Community And Information Source.

The top community for Ford truck, F150, Super Duty, and SUVs owners and enthusiasts

www.ford-trucks.com

Yeah that's the forum. Sorry, I missed your earlier question.

 

[clementine]

Circling back on this one……

Pulled trans. Found a snap ring that was broken. Fixed.

Put back in. No reverse. No 3rd.

Pulled trans. Air checked all holes. Everything checked out.

Replaced valve body.

Bam!! $500 on a valve body apparently was the fix!

It was the first time i drove the truck. She’s got a little pickup! (No joke) i didn’t give it all the beans so i don’t know what kind of top end she has but the low end is impressive.

Thanks FABO!!

 

[ProjectBazza]

Circling back on this one……

Pulled trans. Found a snap ring that was broken. Fixed.

Put back in. No reverse. No 3rd.

Pulled trans. Air checked all holes. Everything checked out.

Replaced valve body.

Bam!! $500 on a valve body apparently was the fix!

It was the first time i drove the truck. She’s got a little pickup! (No joke) i didn’t give it all the beans so i don’t know what kind of top end she has but the low end is impressive.

Thanks FABO!!

With a 429 she SHOULD have plenty of torque, and I’ll admit to being a bit jealous, as while my two sorta-stock 390’s make the right sounds, they’re a little low in the “seat dyno”…..

Congratulations on getting it going!

 

[RustyRatRod]

The 429 is among my favorite engines. It's a BIG bore and a short stroke. Kinda a bigger 340.

 

[clementine]

I’ll send some pics of the engine after cleaning. A bit duuurty

 

[clementine]

But factory ac. Kind of cool.

 

[missing linc]

The 429 is among my favorite engines. It's a BIG bore and a short stroke. Kinda a bigger 340.

Me likey 429 too!

 

[MAXWEDGECHARLIE]

Many Years ago before my 3 Dodge B350 360 TorqueFlite Vans I had a '75 Ford E250 van with 1 ton running gear, 460 and a C6. Nuthin' like a Big Block, anybody's Big Block! The Stop Light Gran Prix was great fun against the rice rockets once I had trained the Autolite quad to pop when I wanted it to. One problem I had was the C6 needed to be warmed up, then revved up before it went into drive. I was told there was a worn bushing in the front pump. I eventually traded it on my first B350, an '86.

 

[clementine]

Me likey 429 too!

Ya, she puts it down. Now i am figuring out the kickdown (pretty sure i put the valve body on so the linkage lines up with that horizantal rod) and the trans will go into high when accelerating but stays in second when at lower cruising.

 

[clementine]

Well I screwed the pooch.

Everything was going pretty good with the trans. Shifted good but it wasn't kicking down when giving her the beans. So I adjust the linkage at the carb by shortening the throttle rod from the gas pedal. Success!! Took it for a ride and everything was going well. Then I punched it going about 50 mph and she kicked down but I think it kicked down to first. Still ran it home ok but now it slips in second and when it does shift its a very soft shift where it was pretty hard before.

Sigh, its just been that way lately. I thought I was a pretty good turner of wrenches........humbled. Hope I didn't screw up the new valve body.

Advice is welcome. I'm about to take it to the trans shop and bend over.

 

[ProjectBazza]

Well I screwed the pooch.

Everything was going pretty good with the trans. Shifted good but it wasn't kicking down when giving her the beans. So I adjust the linkage at the carb by shortening the throttle rod from the gas pedal. Success!! Took it for a ride and everything was going well. Then I punched it going about 50 mph and she kicked down but I think it kicked down to first. Still ran it home ok but now it slips in second and when it does shift its a very soft shift where it was pretty hard before.

Sigh, its just been that way lately. I thought I was a pretty good turner of wrenches........humbled. Hope I didn't screw up the new valve body.

Advice is welcome. I'm about to take it to the trans shop and bend over.

That sucks! Hope it’s easily fixable (I know jack-squat about automatics).

Good luck!

 

[clementine]

Funny how these setbacks can fire me up and sometimes……handcuffed. Mental game is real in this biz.

I’m gonna back off the kickdown completely and see how she reacts

 

[ProjectBazza]

Only thing I’ve ever done on a C6 is install a B&M shift kit in the valve body. Well, that and filters. But I have two of them here (an FE bolt pattern and a 385 bolt pattern) that I’ve been sitting on, waiting for the day when I may need them. Hopefully neither of them need any internal work…..