Installing speed sensor in transmission
Thread Starter
Safety Car
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Installing speed sensor in transmission
Got a 700R4. Had a leaking speed sensor (VSS) oring. Removed the speed sensor and put on the blue GM oring. Lubbed it up with transmission fluid, but the VSS won't press into the transmission housing.
When the oring on the VSS hits the transmission, the VSS won't press in any further.
Is there a special tool or something needed to press the VSS in?
When the oring on the VSS hits the transmission, the VSS won't press in any further.
Is there a special tool or something needed to press the VSS in?
Last edited by samsonb; Feb 16, 2014 at 08:23 PM.
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Got a 700R4. Had a leaking speed sensor (VSS) oring. Removed the speed sensor and put on the blue GM oring. Lubbed it up with transmission fluid, but the VSS won't press into the transmission housing.
When the oring on the VSS hits the transmission, the VSS won't press in any further.
Is there a special tool or something needed to press the VSS in?
Tried to see if I could hammer it in, but not enough room.
Here's what the speed sensor looks like:
And do the gears self align and automatically mesh when installing the VSS, or is it possible the gears could get smashed up?
When the oring on the VSS hits the transmission, the VSS won't press in any further.
Is there a special tool or something needed to press the VSS in?
Tried to see if I could hammer it in, but not enough room.
Here's what the speed sensor looks like:
And do the gears self align and automatically mesh when installing the VSS, or is it possible the gears could get smashed up?
Do you recall the part # of the seal that you purchased?
Thread Starter
Safety Car
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The VSS needs to be properly orientated for the drive/driven to mesh correctly. That I would assume is your issue. If that is the style of VSS you have with the connector in the center the retaining device will show you the correct orientation of the VSS. It might require some "wiggle" but it should NOT require what would normally be considered "force". No hammers!
Do you recall the part # of the seal that you purchased?
Do you recall the part # of the seal that you purchased?
I do know it was very difficult to get the VSS out of the transmission. Had to put channel locks on the outer metal piece and rock and rotate it out.
I used the #15552872 blue oring from the dealer. I had read it was the updated version of the original oring, as the original part number for the oring out of my GM parts catalog isn't good anymore. The original part number from the catalog is #25518664.
Last edited by samsonb; Feb 11, 2014 at 01:59 PM.
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I've got the VSS started into the hole to the point where the oring first hits the transmission. Then I screwed on the retainer so I could get the two VSS square pieces lined up with the two forks on the retainer. But the VSS won't go in any further.
I do know it was very difficult to get the VSS out of the transmission. Had to put channel locks on the outer metal piece and rock and rotate it out.
I used the #15552872 blue oring from the dealer. I had read it was the updated version of the original oring, as the original part number for the oring out of my GM parts catalog isn't good anymore. The original part number from the catalog is #25518664.
I do know it was very difficult to get the VSS out of the transmission. Had to put channel locks on the outer metal piece and rock and rotate it out.
I used the #15552872 blue oring from the dealer. I had read it was the updated version of the original oring, as the original part number for the oring out of my GM parts catalog isn't good anymore. The original part number from the catalog is #25518664.
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[QUOTE=samsonb;1586147524]The plug on VSS is black, the gear is green. I looked it up and looks like the green gear is supposed to have 42 teeth. 3.07 rear end.
The VSS was oriented correctly with the retainer when I had removed it.
Your parts are all correct.
The VSS was oriented correctly with the retainer when I had removed it.
Your parts are all correct.
Thread Starter
Safety Car
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It's definitely the oring. Removed the green gear and tried to install the VSS, and it wouldn't go in. The VSS stops going in when the oring hits the transmission housing. Looks to me like there isn't any clearance for the oring.
What grease is safe to use on the oring? I had put on transmission fluid to lube it for install.
What grease is safe to use on the oring? I had put on transmission fluid to lube it for install.
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It's definitely the oring. Removed the green gear and tried to install the VSS, and it wouldn't go in. The VSS stops going in when the oring hits the transmission housing. Looks to me like there isn't any clearance for the oring.
What grease is safe to use on the oring? I had put on transmission fluid to lube it for install.
What grease is safe to use on the oring? I had put on transmission fluid to lube it for install.
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From: moraga ca
Vaseline will be fine. That's one heck of an oring. I can see why you are having trouble. The orientation is only important so the retainng fork lines up. The gears will mesh with no problem. If pushing doesn't do it, you'll have to get the oring started in one side with a small screwdriver without tearing the oring. Putting pressure on the housing, work your way around. The thing will eventually snap in unless you were given the wrong oring, in which case, you are up a creek. Are you sure the oring was leaking? Usually a leak in that area is caused by the vss leaking, not the oring. They sometimes go bad and leak through the terminals. Mine did that. Good luck.
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Thread Starter
Safety Car
Joined: Jan 2004
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Vaseline will be fine. That's one heck of an oring. I can see why you are having trouble. The orientation is only important so the retainng fork lines up. The gears will mesh with no problem. If pushing doesn't do it, you'll have to get the oring started in one side with a small screwdriver without tearing the oring. Putting pressure on the housing, work your way around. The thing will eventually snap in unless you were given the wrong oring, in which case, you are up a creek. Are you sure the oring was leaking? Usually a leak in that area is caused by the vss leaking, not the oring. They sometimes go bad and leak through the terminals. Mine did that. Good luck.
The oring should be the correct GM blue oring.
I don't see how the VSS could leak other than from the oring.
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From: moraga ca
I've had to plier mine out many times. The oring really seals tightly and I don't think it leaks often. The shaft within the VSS somehow contacts the terminals. The terminals go from inside the VSS to the outside. The plastic seal around the terminals doesn't seal after a few decades. This is a common source of a leak in the VSS area. Mine leaked and a buddy of mine that owns a tranny shop said this happends often. I even tried epoxying mine but that didn't work. Dollars to donuts your problem is the VSS and not the oring.
Last edited by 383vett; Feb 11, 2014 at 11:58 PM.