700r4 Dipstick Length

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Garageman402

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Hi Everyone,

I saw the thread by beachsurburan from 2/21/18 concerning this, and 74 Shortbed mentioned he had one tube 25" and one 33". I measured mine and from the top of the tube to where in goes in the case and it's about 21", two more inches inside would be 23". I'm assuming mine is a 25".

The problem I'm having is the fluid overflowing out the dipstick when filling. I have a Hughes Performance 4 1/2" deep pan (with a drain plug) that adds 2 quarts to the capacity. So on a drain (I let it drain 2 days) normal refill is 6 quarts, and with my deep pan I should be at 8 quarts. The first time I attempted this I tried to put 6 quarts in at once and when I got past 5 it started overflowing out the dipstick tube. So this time I started with 4 quarts, ran it a few minutes, checked the stick, added another quart, checked the stick after adding every quart until 7 quarts. Now it shows an inch below the hash marks and it's still cold. I attempt the 8th quart and when its almost all in, it overflows. I check while running and its way over the hash marks. The dipstick has been cut off at the bottom, it's a rough edge. Is it possible the wrong stick is in here?

It also will blow some fluid out the TV cable when running hot. Almost seems like the vent is plugged. I found the hose and it had debris in the end of it. I cleaned that out, routed it up to the valve cover, sucked on it, it is clear, but couldn't build up a vacuum with the dipstick locked. Also when draining through the drain plug the fluid will "glug" if the dipstick is locked. If the dipstick is loose or removed, there is no glugging.

Any thoughts? Adding 7 quarts with little or no movement on the stick, then all of a sudden it's grossly overfull? I'm afraid to remove the dipstick with it turned off, afraid fluid might run out.

Thanks!!
 

Garageman402

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So I removed the dipstick now that it's cold, it is 22-3/8" long from the flange. The hash mark area is about an inch above that. Seems to me that it barely gets to the top of the case.
 

Matt69olds

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The full mark of the dipstick should be about even with the case/oil pan rail. The overall length doesn’t matter, the length of the dipstick and tube must match.
 

Garageman402

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I found a post on chevelles.com saying the correct fluid level is the top/flange of the oil pan. That will help..........
 

Garageman402

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The full mark of the dipstick should be about even with the case/oil pan rail. The overall length doesn’t matter, the length of the dipstick and tube must match.
Thanks, Matt!! Your post didn't come up when I last posted, guess I should refresh the page before I type, eh?

Yes I knew the tube and dipstick must match, the actual fluid level outside of what any dipstick says is what I needed to know. I need to get a matching set I guess, but would rather not take the bracket off, and I'm not sure a stock bracket will match up to my set-up. I don't really want the flex one that mounts to the firewall. Finding a dipstick that will match my current tube would be ideal!!

Thanks again for commenting, that is the information I was looking for!
 

Turbo4whl

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....I don't really want the flex one that mounts to the firewall. Finding a dipstick that will match my current tube would be ideal!!

Mr Gasket makes several different shape solid chrome tubes w/stick. Summit has them listed.
 

Garageman402

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Mr Gasket makes several different shape solid chrome tubes w/stick. Summit has them listed.
Thanks Wayne, I saw aftermarket versions, not sure where it mounts to. If it mounts to the bell housing bolt then might work. But I solved the problem, see next post.
 

Garageman402

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The full mark of the dipstick should be about even with the case/oil pan rail. The overall length doesn’t matter, the length of the dipstick and tube must match.
Using this information, I put the dipstick alongside the tube, used a zip tie to keep it snug at the curve, and lo and behold, the top of the hot area is right at the oil pan rail!! So this IS an accurate reading. I cleaned up the burred end, it would grab lint from a wipe rag. Still don't know how it got burred, there would be no reason to cut it, maybe it was dropped or something.

I drained out the one quart, bringing it down to 7 added quarts, checked it cold, and it was barely on the stick. Added 8 oz. brought it to a little below the hash area. I took it out, drove 8 miles, went through all the gears, brought it back fully warmed up and the level is exactly in the middle of the hash area!! Perfect!! I probably got a little more than a quart out due to spillage but not more than 8 oz.

Moving forward, apparently the correct way to refill this transmission is start with 2 quarts (4 quarts with a deep pan), then start it and add the rest while running? Or run it then stop and fill more? A standard pan would take 5 quarts for a drain and refill I'm assuming.

Thanks to Matt and Wayne for the input, it's greatly appreciated!!
 
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Garageman402

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Allstar Performance has a line up of racing dipstick tubes/sticks. They are about the same length as the one I have, it cleans up the engine compartment, but makes it hard to service. The tube bolts to the bell housing bolt, so it should fit most any swap.

https://allstarperformance.com/content/1240.pdf



I was looking for something more factory looking, but this one is behind the valve cover, pretty much out of sight. Now that I know the stick is accurate, I will keep it.


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