4l60e no shift attempt to 3rd after rebuild

[Leo330]

There's no spring tension on that valve train, unless you install Transgo's TCC valve or the Fitzall valve (or Sonnax's oversized valve but that requires a reamer to wallow out the bore to fit their os sleeve/valve kit).
Besides, that's not why the 3-4 burned shortly after rebuild.


Yes, Im wondering if you forgot to install the green o-ring at the base of the forward drum so you're starting off in 3rd instead of 1st gear - that's exactly what would happen if you leave that o-ring out...Was it there when you took the forward drum apart?

I did get the green o-ring changed and it was there when I started.

It looks like the check-ball that goes into the 2/4 Servo was not seating. I poured ATF in and it flowed both into the Servo and the main housing. A tap with a punch and hammer seems to have fixed the seating. (Your thoughts on if this is ok way to fix?). I even believe a piece of trash came out, making me feel better that 1) this was a legit problem 2)Wish I had checked this the first time thru.

 

[NickTransmissions]

I did get the green o-ring changed and it was there when I started.

It looks like the check-ball that goes into the 2/4 Servo was not seating. I poured ATF in and it flowed both into the Servo and the main housing. A tap with a punch and hammer seems to have fixed the seating. (Your thoughts on if this is ok way to fix?). I even believe a piece of trash came out, making me feel better that 1) this was a legit problem 2)Wish I had checked this the first time thru.

Yep, that would def cause those 3-4 clutches to get smoked. So you prob were starting out in 1st gear as normal, shifting to 2nd then neutral in 3rd....The punch and hammer is exactly the procedure called for in the ATSG manual so good to go (assuming you re-tested it and it now seals properly).

Have a bidirectional scan tool with you when you go on your first test drive once you have it all back together..I'd also do a pressure test as well....Install Sonnax 4L60E-LB1 to address any issues related to worn boost valves...I never reuse the boost valves in those or 700R4s (or any transmission for that matter).

 

[Leo330]

Solution :

To bring this full circle, I just got the trans back in for the 2nd time and it shifted perfectly 1-2-3-4!!! The check ball going into the 2/4 Servo seems to have been my root problem.

Also, on those 6 miles of testing I appear to have worn .015 off the new frictions. My original gap was 0.060 and it opened to .085. I could also see my new steels had gotten hot. So, I believe the trans was engaging both 2nd and 3rd at the same time and the clutches were taking the brunt of this. Obviously, don't make my mistake and miss this fluid test on the check ball.

There is a lot of talk before this video gets to the point but it shows my solution well.

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Thank you for the feedback and support.

Leo

 

[NickTransmissions]

Solution :

To bring this full circle, I just got the trans back in for the 2nd time and it shifted perfectly 1-2-3-4!!! The check ball going into the 2/4 Servo seems to have been my root problem.

Also, on those 6 miles of testing I appear to have worn .015 off the new frictions. My original gap was 0.060 and it opened to .085. I could also see my new steels had gotten hot. So, I believe the trans was engaging both 2nd and 3rd at the same time and the clutches were taking the brunt of this. Obviously, don't make my mistake and miss this fluid test on the check ball.

There is a lot of talk before this video gets to the point but it shows my solution well.

xc_hide_links_from_guests_guests_error_hide_media

Thank you for the feedback and support.

Leo

Glad you got it sorted out...I thought that I had provided my video on this issue but looks like i didn't.

For those interested in how to test your 3rd accumulator check ball capsule, check out the below - skip to 7:56 to view the 3rd acc check ball capsule segment

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