We'll I've gotten around to looking at my car and it would appear that my
700R4 is perpetually stuck in Drive, even when I start it or put it in park
I can feel it lurch forward. Took it for a drive yesterday and it changes
through all the gears just fine, no funny noises. I've been doing some
research lately and it would seem that alot of people have accidently done
what I have done and worse, I've heard of people hitting reverse at 60 MPH
and guys at junk yards with truck deliberately running down the road then
slamming it into reverse until the truck eventually stops and starts going
in reverse, with a lot of smoke according to eye witnesses.
(All were 700r4 stories) Here was a comment
could have put
So now that I've determined it's not so much a 'no reverse' problem but
always in drive problem my console goes P R N 1 2 3 OD, after reading the
info below it may be a case of the internal linkage on the rooster comb has
jumped a tooth, I'm putting it on the ramps to day and I want to pull the
pan and see what kind of carnage awaits me. Hopefully all will be good and
it will be that simple. I'll post a link to some pics if someone here is
knowledgeable enough to see if the internal linkage looks ok.
Thanks in advance
Here's a post I found in an other forum that gave me some hope:
Since you said it's stuck in "drive", I'm assuming it's an automatic. Most
likely it's the 700R4 overdrive, but the following advice is good on any GM
automatic. First, crawl under while someone runs the shift lever through the
gears(while holding the brake of course so you don't get run over) and make
sure the linkage to the drivers side of the transmission is all still hooked
up. If so, it's internal. Then you need to go to a parts store and buy a
filter kit which includes a pan gasket and filter(you'll be pulling the pan
so just as well change the filter while it's off). Take the pan off, with a
drain pan underneath to catch the fluid of course(leave two bolts in and
remove the rest to allow the pan to drop at an angle and slowly loosen the
remaining two bolts to drain the fluid out of one corner before taking the
pan off completely). Then, remove the pan and look at the inside of the
transmission case where the shift linkage shaft goes in. There is a deal on
there called a "rooster comb" with detents that help each gear to be felt.
This "rooster comb" is held onto the shifting shaft with a nut. The nut may
have come loose. Also, there is or should be an 's' shaped "wire" link from
the rooster comb to what's called the manual valve, which is on the driver's
side of the valve body(the valve body is the square-shaped cast iron piece
that's bolted to the bottom of the aluminum transmission cast with a dozen
or more bolts). If the nut on the shift shaft has come loose, this s-shaped
link may have fallen off. This would cause the manual valve to not be moved
when shifting and the transmission to remain in one gear. If all this looks
and moves like it's supposed to, then the problem is deeper and will need to
be taken to someone who can check the tranny's internals. If you do find the
problem, fix it, clean and reinstal the pan(use just the gasket with no
sealer) and refill the transmission fluid and you'll be back in business.
Hope this helps!
Hey guys just got done pulling the tranny pan, the oil was very BROWN but
still looked red, it didn't smell burnt, if anything I would have to compare
it to smelling like latex paint. Bare in mind the fluid hasn't been changed
since summer '96 and I probably put 30-40 K on it since then. Here's a link
of the first group of pics, I'd really love some feed back, tell me what you
think about the tranny fluid colour and I've included pics of the rooster
comb, if you need different angles, please email me or post them here and
I'll gladly oblige if you can help be with this diagnosis.
Here's the site with my pics so far
Thanks again to all.
From that angle, it looks okay to me. This is going on my memory of
the last time I had the pan off my 4L60E (decendant of your 700R4).
But no need to be rude to Mike, he was talking about the linkage that
connects the steering column to the transmission. Should be on the
left side of the car and go from, well--you know--the steering column
to the transmission. If it's somehow rusted out or slipped loose, you
could be stuck in gear.
That's what I'm hoping. I see somethings bent after reviewing the pics,
hoping someone can fill me in. Could debris in a value make it so that a
700r4 is always in drive and can't engage into reverse?
Well, I have seen you symptoms quite a few times over the years and even
with a floor shifter, it has always been a linkage problem and in the
cases of the ones I have seen, it was external to the guts of the
Sometimes it is the simple things....
Sure sounds like a linkage problem... does park acatually lock?
You should be able to disconnect the linkage and verify that it shifts properly
or not by manipulating the leaver at the side of the tranny. Depending on your
jack/pit setup... pull/push over a pit or jack the drive-wheels off the ground
and then manually manipultate the tranny-shifter w/o the linkage attached.
I ran it thru the gears and looked at the rooster comb in the pan seemed to
work fine there, but there is a shaft that runs from that linkage setup to
the inside of the tranny which could have slipped a spot.
The parking rod does engage when it's in park but you can feel it's still in
It's a real bitch to push out of my garage too, still in gear, can get it in
neutral even when it's off.
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