apex2112

I'm trying to finish up the rebuild on my 4l60e and when I put in the 2-4 servo to test that I get the 1/16 to 1/8 movement, I only get about .010/.015.
I have a new AC Delco reverse drum and new Raybestos wide 2-4 band.
The band is attached to the case and ancor pin, the drum turns fine.
Do I just grind the servo pin to get the 1/16 to 1/8 movement?
Just seems strange to have to grind the stock servo pin

ROCNDAV

iTrader: (100)

Did you install anything else like a shift kit that would have had you install washers?
How are you checking the movement?

mrvedit

It does seem unusual that the stock pin would be so much too long with those parts.
Even with a brand new reverse drum and wide band, I usually install one Transgo servo shim to get a nice tight servo.

Be sure the servo pin is centered in the eyelet of the band; it might be pushing on the edge with just finger pressure. I usually install the servo before the pump so that I can see that the servo and band are properly installed and engaged.

apex2112

Ted, I might just go ahead and pull the pump back out and double check that the pin is engaging the band correctly.
Will I need a new pump gasket and stator sealing rings?

ROCNDAV

iTrader: (100)

You shouldn't have to replace them since you haven't run it yet.

mrvedit

Right.
If you keep the pump out for any extended amount of time (15 minutes?) I would put a resizer back on the sealing rings.
If I don't have an official resizer handy, I just use plastic from a 2L bottle and some hose clamps.
Ted.

apex2112

Well I pulled the pump back out and the band is attached to the case correctly and ancor pin is engaged.
When I put the servo pin in and look down into the case now that pump is removed, I can see that it aligns correctly with the band.
I use a dial indicator to check movement per the instructions from Sonnax.
I see in the ATSG manual they show 3 different pin lengths, by going with the wide band does it require a different pin?

mrvedit

I hope you didn't mind my suggestion to pull the pump back out; better safe than sorry. And hopefully it wasn't hard that this point.

I guess it is time to grind down the pin then.
Since the Sonnax instructions for the 4th gear servo mention grinding down the pin, this must be common.

apex2112

No worries about pulling the pump, this being my 1st build I want to be extra sure it's right.
Just wish a pro builder could chime in if it is a common thing to grind the pin.
In the ATSG manual they list 3 different lengths, mine was the middle of the 3 lengths.
If I had the shortest one it would have been very close to the correct amount of movement I think.
I'm going to grind the pin we will see, I'll report back.

apex2112

Well I took .065 off the pin, now I'm getting .075 movement.
The difference in length between the shortest pin and the one I have is between .050/.070, I wonder if the band I got was made for the shortest pin.
That's the only thing that makes sense to me, because I had the same issue with the stock servo setup and the Sonnax/Corvette servo

apex2112

Well, got the trans back in the truck and it's shifting fine so grinding the pin seems to have been the correct thing to do.
Many thanks to Ted for his help along the way answering my questions, you sir are a class act!

mrvedit

Glad to hear that you got the trans rebuilt and installed and that it is working well. And thank you for the kind words.
Ted.