4L80E output shaft question
#1
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there seems to be a couple diff output shafts (2W drive)
early have short splines and o ring, later longer splines maybe????
anyway, on the short spline with the o ring, do you need a yoke with the hollow area to slide over the seal, or can you just use a reg 400 yoke
what does the o ring do anyway-i remember on the old 400's, they used it with a yoke with a hole in it to let air out when it slid-sure caused a lot of leaks when it was used in non o ring trans, lol
early have short splines and o ring, later longer splines maybe????
anyway, on the short spline with the o ring, do you need a yoke with the hollow area to slide over the seal, or can you just use a reg 400 yoke
what does the o ring do anyway-i remember on the old 400's, they used it with a yoke with a hole in it to let air out when it slid-sure caused a lot of leaks when it was used in non o ring trans, lol
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#8
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On a stock 4L80E the yoke is typically bolted on. The o-ring seals the yoke so ATF doesn't leak by the splines and out the back of the bolt on yoke.
Same as a truck style TH400.
You can use a stock TH400 yoke, the issue is that if you look at the spline engagement, you are giving up some engagement to have the proper amount of travel for normal yoke slip.
We machine the output shafts so a normal yoke will go past the splines about 3/4", so there is always complete or near complete spline engagement.
Same as a truck style TH400.
You can use a stock TH400 yoke, the issue is that if you look at the spline engagement, you are giving up some engagement to have the proper amount of travel for normal yoke slip.
We machine the output shafts so a normal yoke will go past the splines about 3/4", so there is always complete or near complete spline engagement.
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On a stock 4L80E the yoke is typically bolted on. The o-ring seals the yoke so ATF doesn't leak by the splines and out the back of the bolt on yoke.
Same as a truck style TH400.
You can use a stock TH400 yoke, the issue is that if you look at the spline engagement, you are giving up some engagement to have the proper amount of travel for normal yoke slip.
We machine the output shafts so a normal yoke will go past the splines about 3/4", so there is always complete or near complete spline engagement.
Same as a truck style TH400.
You can use a stock TH400 yoke, the issue is that if you look at the spline engagement, you are giving up some engagement to have the proper amount of travel for normal yoke slip.
We machine the output shafts so a normal yoke will go past the splines about 3/4", so there is always complete or near complete spline engagement.
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i've heard you had to cut down the yoke so that it will be able to slide in and out enough as the rear articulates. with the car sitting level and the driveshaft bolted to the diff with the yoke slid into the trans, how much should the yoke be able to slide in? this is an older style 4l80e(no 12 o'clock bolt hole), stock rear, stock driveshaft, and a th400 slip yoke that measures 7.5''(the smooth part that actually slides into the trans is 5''). thanks for any help
#12
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There is a pic on my TH400 page that may help.
http://www.jakesperformance.com/TH400_Components.html
The TH400 output shafts are essentially the same as far as the yoke is concerned.
You can see the o-ring groove and how close it is to the splines.
Depending on application you need about 1" of yoke slip.
As you can see in the pic you would be giving up almost an inch of spline engagement.
We machine the shafts so that the yoke can go further in the trans and retain full spline engagement. This assures more power capability and less likely to have driveline vibrations.
http://www.jakesperformance.com/TH400_Components.html
The TH400 output shafts are essentially the same as far as the yoke is concerned.
You can see the o-ring groove and how close it is to the splines.
Depending on application you need about 1" of yoke slip.
As you can see in the pic you would be giving up almost an inch of spline engagement.
We machine the shafts so that the yoke can go further in the trans and retain full spline engagement. This assures more power capability and less likely to have driveline vibrations.
![](http://www.jakesperformance.com/images/dscn0105.jpg)
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ok that helps. so say with the driveshaft installed onto the car, you should be able to unbolt it from the rear and it should slide about 1'' into the trans before stopping? so if it only slides .5'' just hack saw .5'' off the end of the yoke so it'll slide in a full 1''? sorry, i just want to be sure i'm not ruining the yoke by not doing it right.
#14
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ok that helps. so say with the driveshaft installed onto the car, you should be able to unbolt it from the rear and it should slide about 1'' into the trans before stopping? so if it only slides .5'' just hack saw .5'' off the end of the yoke so it'll slide in a full 1''? sorry, i just want to be sure i'm not ruining the yoke by not doing it right.
The average consumer thinks they should just use a hacksaw to fix a clearance issue.
You can cut down a yoke but there are correct ways of doing it and I would recommend doing things the correct way.
USUALLY I recommend installing the yoke until it bottoms, pulling it out 3/4"-1" and then cutting the driveline to fit.
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so your saying shorten the driveshaft instead of the the yoke. what would be the issue with cutting down the yoke instead of the driveshaft? i understand there's a right and wrong way to everything, just trying to understand what would make cutting the yoke, the "wrong way".
#16
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so your saying shorten the driveshaft instead of the the yoke. what would be the issue with cutting down the yoke instead of the driveshaft? i understand there's a right and wrong way to everything, just trying to understand what would make cutting the yoke, the "wrong way".
Look at how the original end looks, make your newly cut end look the same.
#19
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Would you still think the same thing when I voided your warranty on a transmission that had thrust washer damage?
#20
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curious if the later output shaft with the long splines would swap in an earlier trans, or was there a change in something-then you could use a yoke with the long spline and have max engagement
i usually meas the distance from trans to rear with full weight on the rear, then with it hanging, see how much the yoke will move
hanging loose it will usually be closer-i try and fit them as tight as possible, but not to tight where it would ever bottom out
i usually meas the distance from trans to rear with full weight on the rear, then with it hanging, see how much the yoke will move
hanging loose it will usually be closer-i try and fit them as tight as possible, but not to tight where it would ever bottom out
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