700r4 locking up!
Thread Starter
Instructor
Joined: Jun 2002
Posts: 231
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From: 80/680 junction Ca.
700r4 locking up!
Ok!
Tooling down the road and come upon some traffic, slow down to a stop, start to move ahead and bam! rear end starts hopping then just as fast as it stopped I start moving again, then Bam! again. I slam the shifter into first and creep off the freeway, first is fine, second is no deal. There's a tranny shop down the road so I creep over there and the guy say's it sounds like hard parts. Great! The small planetary maybe. I crept home in first and I'm now going to drop the pan when it cools down. It's an 87. Any thoughts? I tried to run in drive in front of the house and same thing happens, it just locks up at the shift into second, and as soon as the wheels stop it unlocks back into first.
Tooling down the road and come upon some traffic, slow down to a stop, start to move ahead and bam! rear end starts hopping then just as fast as it stopped I start moving again, then Bam! again. I slam the shifter into first and creep off the freeway, first is fine, second is no deal. There's a tranny shop down the road so I creep over there and the guy say's it sounds like hard parts. Great! The small planetary maybe. I crept home in first and I'm now going to drop the pan when it cools down. It's an 87. Any thoughts? I tried to run in drive in front of the house and same thing happens, it just locks up at the shift into second, and as soon as the wheels stop it unlocks back into first.
Instructor
Joined: May 2004
Posts: 163
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From: machesney park il
i think lockup convertors have a solinoid that locks and unlocks the convertor.i had the same thing happen on my 91 chevy work car,it had a lockup convertor also.turned out to be the lockup solinoid gone bad.replaced that and everything was fine.i dont know where it is on a 700r4,but it was not expensive to replace.
Instructor
Joined: May 2005
Posts: 162
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From: Lady Lake FL
A bad lock-up solenoid wouldn't cause the trans to lock up and slide the tires. Something wrong with the 2-4 band maybe? Parking pawl (? I think that's what it's called, the arm that holds the output shaft from turning when in park)? Let us know what you find when you get the pan off. 
KC
KC
Race Director
Joined: Feb 2004
Posts: 12,518
Likes: 19
More likely than not, you broke a planetary gear set. When they break, they usually tear up a bunch of parts. The good news is, the vette trans uses the same hard parts as a similar year 700r4. A $50 donor core will supply most, if not all of the hard parts needed to solve your problem. You will need a rebuild, of course. The hard parts are no big deal. Super easy to get and cheap! If you prefer new hard parts, they are many hundreds of dollars.
Thread Starter
Instructor
Joined: Jun 2002
Posts: 231
Likes: 0
From: 80/680 junction Ca.
Got the pan off today. There were about 10 very small pieces of metal in the pan, they all look the same. I'll have to take a picture, they look like small teeth from a ring gear to me, but very small. The fluid looks bad with lots of metallic dust in it, lots. I'll get the thing out of the car tomorrow and go from there.
