Shifting P RND321, strange problem

[Locomoko]

OK here is one for the forum...

Recently rebuilt my Burbs 4L80e transmission, with standard clutch packs & steels, o-rings, etc. using a video and ASTG guide. The build went well without snags... the instructions were good and the video had good tips. The re-assembly also went along according to the instructions with the key progress checks passing, so I think the build was successful. However, there is a problem that the forum could possibly steer me as to where to look for a solution. :D

The engine starts in Park and Neutral as it should. The shift lever won't go to 1st and there is no reverse (with shift lever in reverse). Also when started in Neutral it is immediately engaged in a forward gear (with shift lever in Neutral).

The shift cable adjustment was done (unlock the white clip, move ten times, then re-lock) but that didn't change my shifting problem. :(

I thought I had this thing licked, now I need help please, anyone experienced? and thanks for reading the post. :confused:

[Robyn]

Sounds like an issue with the manual valve inside.

The manual valve may be connected to the crank assembly (goes through the case) improperly.

Drop the pan and be sure things are connected correctly.

If the indexing was off then this would explain why it wont go to 1 and R

With the pan off so you can watch whats going on disconnect the cable so you can move the crank manually.

Get the trans in Park and then reconnect the cable. Now have a helper move the lever to R and then be sure the manual valve is actually in the R detent on the "Rooster comb" inside the tranny ( device with all the notches that that park rod hooks to) Proceed to check all the locations and be sure the thing will reach all positions.

Now, did you remove the park rod and detent (rooster comb) from the tranny??

If you did it may be possible to have reversed the direction of the detent so its timed wrong.

Not sure on a 4L80. Most of the older ones wont fit backwards.

Also make sure the manual valve spool has the pin on the comb in the notch at the one end. The notch is basically a groove all the way around the spool and this allows the spool to be moved back and forth by the controls.

The other issue could be a solenoid not working right.

Not being able to see the little critter up close and personal make this sort of diagnostics tough.

Keep us posted

Robyn

[Locomoko]

Hello Robin,

Thanks for the tips, I had a feeling my next step would be to remove the pan and observe the index/detent operations.

FYI I didn't remove the rooster and connection rod, and the solenoids were checked for resistance readings (all in spec).

Thank you Robin, it is sooo good to have a helping hand when you need it, Aloha Stuart :)

[DennisG01]

Aloha Stuart :)

There's the problem! You've probably heard about people using vegetable oil in their trucks and you thought to yourself "Hey, why don't I try pineapple juice?". ;)

[Locomoko]

Good suggestion, no really, actually it has been tried, :eek: then Exxon bought the intellectual :rolleyes: rights to it from Dole and that killed it. One more for the fat cats. :(

[DennisG01]

Good suggestion, no really, actually it has been tried, :eek: then Exxon bought the intellectual :rolleyes: rights to it from Dole and that killed it. One more for the fat cats. :(

Things never cease to amaze me!