c4 shifting question

mkaenel · Jun 21, 2008

I just drove the truck around the cul de sac and it up shifts from 1 to 2 and then 3 really quickly. About every 5 feet. It doesn't seem to be holding 1st gear at all.

It is a brand new trans rebuilt by Art Carr and it sat in my garage for about a year before it was put in.

It's weird because the first time I drove it (about 2 months ago) it worked fine up and down the block.

Any ideas?

mkaenel · Jun 21, 2008

Actually after doing it again it seems to be slipping from 1st gear to neutral and the back into gear... and then back to neutral.

Any Ideas?

Viperwolf1 · Jun 21, 2008

Fluid level good?

doran4x · Jun 21, 2008

Vacuum modulator hooked up?

mkaenel · Jun 21, 2008

two really good things to double check... thanks.
Matt

oleguy74 · Jun 21, 2008

bought my 74 new in 74.same trbl from factory.ford rebuilt it once ,re-did it 3 more times.same old stuff.i think you have a case ,or valve body trbl.it would last about two mounths on a re-build.although it never broke down in all these years.put a new one in two years ago.trouble gone.

mkaenel · Jun 21, 2008

I honestly think it is a low fluid issue. Because it worked fine the first time I tried out the new drive train (down the street and back).

Since then I have had to drop the trans pan and reseal it because of a leak. I will be checking the level tomorrow.

Thanks,

Matt

oleguy74 said:
bought my 74 new in 74.same trbl from factory.ford rebuilt it once ,re-did it 3 more times.same old stuff.i think you have a case ,or valve body trbl.it would last about two mounths on a re-build.although it never broke down in all these years.put a new one in two years ago.trouble gone.

BronCowie · Jun 21, 2008

You can try adjusting your vacuum modulator, clockwise on the screw, to tighten up the tension which makes it shift later rather than sooner. Give it one or two turns and then try it out.

Mine sat for a while too (3 years) and finally worked itself out after ~1,000 miles to get things lubed again. (warning - C4 trans rookie advice)

Viperwolf1 · Jun 21, 2008

The modulator will not cause your C4 to slip. If it was working good prior do not adjust the modulator now.

BronCowie · Jun 21, 2008

Viperwolf1 said:
The modulator will not cause your C4 to slip. If it was working good prior do not adjust the modulator now.

Yep... agree. Early shifting could be cured with a VM adjust, slipping is something else altoghter.

c4 shifting question

mkaenel

Bronco Guru

mkaenel

Bronco Guru

Viperwolf1

electron whisperer

doran4x

Sr. Member

mkaenel

Bronco Guru

oleguy74

Bronco Guru

mkaenel

Bronco Guru

BronCowie

Old Timer

Viperwolf1

electron whisperer

BronCowie

Old Timer

Similar threads