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Hard shift/Lucas stop leak


LuckyKenny

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When i completely stomp on it in first gear and when it shift's into second it hesitates sometimes. Same with 2nd to 3rd

 

My tranny fluid looks burnt and i honestly don't know what to do.

 

I bought a 4 dollar thing of lucas stop slip tranny fluid, that was on sale, its a little bigger than a quart like 28 ounces or something. It was kind of an impulse buy

 

Should i somehow drain the tranny fluid or just leave it alone and keep my mouth shut?

 

Tranny is a 3 speed no overdive, with a shift kit i was told

 

It doesnt change gears smooth, almost like someone kicking a door

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Kenny, has it always been a hard shift? A shift kit by design seperates the gears more for a crisper shift. By design a trans holds the current gear, shifts to the next, then release the now previous gear. A 7004R trans is an overdrive with a lockup. The shifts are controlled by what looks like a kickdown bracket is in fact a pressure regulating cable. Improper adjustment kills these things quick. Setting them up is an art. I set my customers with a pressure guage.

 

Andy

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It's always been slamming into gear

 

When i'm just about to max out rpm's in first and it shifts into second it hesitates a little, maybe loss of traction?

 

When i floor it from 0 power braking i chirp first and second.

 

I have literally done that 2 times sinse i've got new tires, now i gun it at 5 or 10 so i dont spin too bad

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The shift kit in will cause hard shifts . Also you might check to make sure the vacuum line is connected to the modulator . The modulator can go bad also . Bad or no vacuum can cause late shifts if the ole memory banks are working correctly .

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it sounds like the vacuum modulator might be having some issues.

 

if it's adjustable it might need to be adjusted down a little bit.

 

shift speed is controlled by OUTPUT shaft speed (Rear tires) not engine speed.

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Kenny, it sounds like there is an issue with the TV cable. The more the cable comes out on throttle, the more line pressure is released. I would try shortening the cable an 1/8th inch or so.

 

There is no vacuum connected to a 700, it is all done by the TV cable and the governor.

 

Andy

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Sounds like the TV spool is stuck in the valve body causing a high pressure situation at low throttle input. If it's not shifting til late this is often the cause. Take the cable loose from the carb and give it a bunch of quick tugs to try and free the spool.

 

I would get a gauge to hook up to the transmission if it was me, that would tell you in a minute. Something like this: Gauge test assembly

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" Tranny is a 3 speed no overdive, with a shift kit i was told "

 

 

Doesnt look like its a 700R4 guys . I stick with the modulator/vacuum problem .

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lucky kenny.. need to stick your head under the car and look at the transmission oil pan, it'll be behind the front tires.

 

if it's totally square, with one corner knocked off, it's a TH350

(it'll also have a can sticking out the passenger side straight back with a vacuum line attached to it)

 

I'm not sure what a 400 pan looks like off hand, but you can tell a 400 from a 350 by the vac. modulator stick out sideways towards the passenger side of the car.

 

the 700r4 has a completely square pan.

 

link to transmission pan shapes

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AlllllllRighty Kenny, we are going to ask you to jack it up, put it on stands and get some pics of the trans. I based everything I said on your signature, a 7004R. A 4 speed overdrive trans with a lockup. A TH350 does a similar thing but does it in a violently different way.

 

Go get the jack, Jack.

 

Ondy

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