4L60e Forward Sprag height difference

[Leo330]

As I continue into rebuilding my 1993 K1500 trans, I found that the existing forward sprag had a damaged cage and three of the dog bones fall out.

I purchased a new forward sprag assembly from wittrans.com (https://www.wittrans.com/New_link_parts.php?type=4L60E&section=32_input&part=648), and the correct part ID can be difficult. Some reading led me to believe you could and should use a later design with 29 elements. Based on this I ordered part no U74648C.

However, in all videos I see nothing showing a height change. I'm wondering if they sent me the wrong part. My original part is on the left and the replacement on the right. While similar you can see the right one is taller and has a different face design. I'm nervous about swapping this one in and having troubles. Can someone provide some guidance? Maybe they just had this part in the wrong bin?

You must be registered for see images attach

Thank You,
Leo

 

[NickTransmissions]

As I continue into rebuilding my 1993 K1500 trans, I found that the existing forward sprag had a damaged cage and three of the dog bones fall out.

I purchased a new forward sprag assembly from wittrans.com (https://www.wittrans.com/New_link_parts.php?type=4L60E&section=32_input&part=648), and the correct part ID can be difficult. Some reading led me to believe you could and should use a later design with 29 elements. Based on this I ordered part no U74648C.

However, in all videos I see nothing showing a height change. I'm wondering if they sent me the wrong part. My original part is on the left and the replacement on the right. While similar you can see the right one is taller and has a different face design. I'm nervous about swapping this one in and having troubles. Can someone provide some guidance? Maybe they just had this part in the wrong bin?

You must be registered for see images attach

Thank You,
Leo

The sprag assembly on the right has the forward clutch hub/outer race upside down.

All 4L60E forward sprags are 29 element...That was intro'd in 1987 or 88. Previous sprags were 24-element and Jan - May of 1982 there was a 7-element roller clutch assembly (it was phased out as part of a mid-year change)

 

[Leo330]

The sprag assembly on the right has the forward clutch hub/outer race upside down.

All 4L60E forward sprags are 29 element...That was intro'd in 1987 or 88. Previous sprags were 24-element and Jan - May of 1982 there was a 7-element roller clutch assembly (it was phased out as part of a mid-year change)

Nick,

Do you have a preferred source for parts? I learned of WIT, thanks to a local shop but I'm not sure I'm completely happy with their parts.

I flipped just like you said, but there was some light rust on the part, along with some on the races. Giving them the benefit of the doubt maybe someone retuned this in poor condition to them. I e-mailed and ask for a replacement. It roils a bit rough after re-assembly. Rougher than my original with the bad cage.

Thanks for the help.

Leo

 

[Leo330]

If anyone is interested this is the noise difference, but also you can feel the roughness.

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[NickTransmissions]

Nick,

Do you have a preferred source for parts? I learned of WIT, thanks to a local shop but I'm not sure I'm completely happy with their parts.

I flipped just like you said, but there was some light rust on the part, along with some on the races. Giving them the benefit of the doubt maybe someone retuned this in poor condition to them. I e-mailed and ask for a replacement. It roils a bit rough after re-assembly. Rougher than my original with the bad cage.

Thanks for the help.

Leo

Hi Leo,

Most of my 4L60E hard parts come from customer core trade-ins that I tear down or from 4L60Es laying around in the junk yard.

You cannot use the old outer and inner race that held the failed sprag (at least I never do). Ill grab a good used sprag gear set replace the element itself with new.

Replace the sprag element with a new Borg Warner version and take 400g sand paper or emery cloth and go over the inside of the outer race until cross hatching is established. Install the new element - verify correct sprag rotation then dunk thw whole assy in transmission fluid before installation into the forward drum.