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Help!!! 4R70W issues

lars

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Is it possible that the output from the transmission to transfer case is slightly too long and causing a bind when the adapter is bolted to the transfer case?
 
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1buckeyefan1

1buckeyefan1

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go back and reset lokar linkage step by step, cheap check.

I think it looks pretty good from inside the pan.

4r70w lokar.jpg


The only step that was missing was reinstalling the kickdown spring. My 4r70w doesn't look like this.. i assume this is for a model with a manual kickdown mechanism?

Lokar Fig11.JPG
 
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1buckeyefan1

1buckeyefan1

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Whenever you try to put the transmission in park with the transfer case in neutral, you should shut the motor off first.

thanks, i think this is they key thing I was unaware of. when i reattached the transfer case, my twin sticks were back in neutral. I assume that was the horrendous park pawl noise that I captured in my video?
 
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1buckeyefan1

1buckeyefan1

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Well transmission pan put back on.. refilled, ran it through the first set of gears and no noise. reversed it back into the shop and boom... same grinding noise when I came to a stop, then attempted to put it into park.

I'm thinking it's still the park pawl, but for the life of me cant figure out why? It seems to make more noise when i try to go reverse to Park I did notice it's idling pretty high (assumed since the O2 sensors aren't in yet). Could the pawl be grinding due to a high idle? I'm going to start testing my theory by turning it off in gear, then going to park.

Or could the Lokar shift linkage being out of adjustment cause it? I even checked the detents and they were spot-on when i ran through the gears and the pan off???
 
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1buckeyefan1

1buckeyefan1

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Is it possible that the output from the transmission to transfer case is slightly too long and causing a bind when the adapter is bolted to the transfer case?

Pretty sure it's definitely coming from the transmission at this point...
4R70W doesn't have a kickdown.

thanks for confirming Viper.

Any ideas if/why a high idle might be causing the pawl to grind yet? I also noticed that it really wants to jump into gear now.. i assume due to the high idle.

I'm not sure how to even turn the idle down since it's using the Explorer PCM (??) I've disconnected the battery overnight. I have another PCM that EFIguy made for me..

It's still odd that it didn't grind for the first few weeks, then started grinding as I was backing it up and going into P
 

Viperwolf1

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Pretty sure it's definitely coming from the transmission at this point...


thanks for confirming Viper.

Any ideas if/why a high idle might be causing the pawl to grind yet? I also noticed that it really wants to jump into gear now.. i assume due to the high idle.

I'm not sure how to even turn the idle down since it's using the Explorer PCM (??) I've disconnected the battery overnight. I have another PCM that EFIguy made for me..

It's still odd that it didn't grind for the first few weeks, then started grinding as I was backing it up and going into P
I would look for a vacuum leak causing the high idle. The ECM controls the idle speed and you can't adjust it. It should be throwing a code if the ECM is not seeing rpm that it expects though. Maybe check for that. Did you have Garry add a high idle circuit to the harness? Maybe something is wrong there?

The park pawl is really simple on a 4R70W. It's at the bottom of the case and easy to get to. There should the a small spring (not the one on the rod) that holds the pawl down to the bottom of the case unless the linkage is pushing it up. Maybe the spring is missing and the pawl is bouncing into the ring?
 

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1buckeyefan1

1buckeyefan1

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I would look for a vacuum leak causing the high idle. The ECM controls the idle speed and you can't adjust it. It should be throwing a code if the ECM is not seeing rpm that it expects though. Maybe check for that. Did you have Garry add a high idle circuit to the harness? Maybe something is wrong there?

The park pawl is really simple on a 4R70W. It's at the bottom of the case and easy to get to. There should the a small spring (not the one on the rod) that holds the pawl down to the bottom of the case unless the linkage is pushing it up. Maybe the spring is missing and the pawl is bouncing into the ring?

Yep, i checked the pawl today when i had the pan off. I was worried after the beating it took, but the pawl and spring looked in pretty good shape yet. I went through the gears and the pawl locked/unlocked pretty successfully. I always knew there was some sort of park lock, had no idea what a park pawl was until today though ;)

Any idea what would cause the transmission to still be spinning while the vehicle is stationary? Pretty sure it's been the pawl all along when I attempted to go from R->P and got the grinding noise.

I'll keep hunting for the reason for high idle. No related codes today except for p1460 (wide open throttle a/c cutout circuit) and p1703 (brake switch out of self test range)
 

Viperwolf1

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If the transmission is not in park, the output shaft will spin unless something stops it. Usually that something is the rear tires being attached to the ground. However, if the transfer case isn't connecting the trans output to the driveshaft that output shaft will spin.

There is a possibility that the input gear of the tcase could have been installed backwards. This would give no high range on the rear axle. It would act just like it was in neutral if the levers were in rear high. You wouldn't be able to drive it though until you engaged the front axle in high range.
 
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1buckeyefan1

1buckeyefan1

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If the transmission is not in park, the output shaft will spin unless something stops it. Usually that something is the rear tires being attached to the ground. However, if the transfer case isn't connecting the trans output to the driveshaft that output shaft will spin.

There is a possibility that the input gear of the tcase could have been installed backwards. This would give no high range on the rear axle. It would act just like it was in neutral if the levers were in rear high. You wouldn't be able to drive it though until you engaged the front axle in high range.

Hmm. This all started a few weeks ago when i first starting shaking things out...I would back the bronco into my shop and put it into park. Got a crazy grind.. which I'm pretty certain is now the pawl.

The neutral transfer case was definitely a red herring today. The pawl noise got worse through the rest of the gears.. since it was in neutral. makes sense.

Now I'm back to pawl noise when going from R->P after backing up. If i recall, it's sorta intermittent, then stops. Maybe I simply need to wait a few seconds before putting it into park? I've got no exhaust on it yet, so i'm usually in a hurry when i put it into reverse, then park.. i don't really want it idling for awhile in the shop.

I think the transfer case is ok, since i now am moving in rear/high.
 

Broncobowsher

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If the transmission is not in park, the output shaft will spin unless something stops it. Usually that something is the rear tires being attached to the ground. However, if the transfer case isn't connecting the trans output to the driveshaft that output shaft will spin.

There is a possibility that the input gear of the tcase could have been installed backwards. This would give no high range on the rear axle. It would act just like it was in neutral if the levers were in rear high. You wouldn't be able to drive it though until you engaged the front axle in high range.
Just got to this thread and this is what I was about to type in. I'll rehash a few things as well...

If the transfer case is in neutral, the transmission output shaft will spin at engine speed unless in park. There will be RPM, just no meaningful driving force. The wet clutch packs have stacks of clutches with oil over them. Think of putting a wet towel on a table and pulling on it. There will be a little force trying to pull the table across the floor. But if you clamp that wet towel to the table, they are locked together. That is the wet clutch pack. So having the transfer case in neutral and the transmission out of park the output shaft will be spinning. Tossing the shifter into park will bounce the parking pawl and make a bunch of noise. That is expected. The typical shifting between high and low range for me typically involved coming to a stop, DO NOT RELEASE THE BRAKES, go to park, move the transfer case levers. get to neutral and if it won't go into gear then a little release of the brakes to get a tiny roll to get the gears to line up. Once the transfer case is in gear you can shift out of park. If you get it wrong, and the transfer case goes into neutral without the transmission in park, the only fix is to turn the engine off.

Now for that extra neutral on the transfer case. The input gear can be installed backwards. Comes up a couple times a year on this board. And that gear had to be moved to the new sped shaft when the transmission was swapped. When that happens you get a perfectly normal low range, and a normal front output in high range. But rear output in high range is always neutral reguardless if the shifter is in gear or neutral.
 

doran4x

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Did you shave off enough material from output shaft on transmission?


Sent from my iPhone using Tapatalk
 
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1buckeyefan1

1buckeyefan1

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Just got to this thread and this is what I was about to type in. I'll rehash a few things as well...

If the transfer case is in neutral, the transmission output shaft will spin at engine speed unless in park. There will be RPM, just no meaningful driving force. The wet clutch packs have stacks of clutches with oil over them. Think of putting a wet towel on a table and pulling on it. There will be a little force trying to pull the table across the floor. But if you clamp that wet towel to the table, they are locked together. That is the wet clutch pack. So having the transfer case in neutral and the transmission out of park the output shaft will be spinning. Tossing the shifter into park will bounce the parking pawl and make a bunch of noise. That is expected. The typical shifting between high and low range for me typically involved coming to a stop, DO NOT RELEASE THE BRAKES, go to park, move the transfer case levers. get to neutral and if it won't go into gear then a little release of the brakes to get a tiny roll to get the gears to line up. Once the transfer case is in gear you can shift out of park. If you get it wrong, and the transfer case goes into neutral without the transmission in park, the only fix is to turn the engine off.

Now for that extra neutral on the transfer case. The input gear can be installed backwards. Comes up a couple times a year on this board. And that gear had to be moved to the new sped shaft when the transmission was swapped. When that happens you get a perfectly normal low range, and a normal front output in high range. But rear output in high range is always neutral reguardless if the shifter is in gear or neutral.

Thanks, this is probably the best explanation of how the clutch packs work. makes complete sense now why it was still spinning a bit despite being in park.

I'm thinking the transfer case is still set up correctly (I removed the inspection plate yesterday and watched it go into all gears).. it was a boneheaded mistake that put it in neutral when i reassembled my twinsticks. I've got motion back now. Just can't figure out why I'm still getting noise from the pawl when I go from Reverse->stop->Park. I'm going to test it out a bit more today and will report back.
Did you shave off enough material from output shaft on transmission?


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I believe so. I followed Chuzies thread and have slid the transfer case on now 3 times and it mates up to the transmission housing nice and tight every time.
 
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1buckeyefan1

1buckeyefan1

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Well, I took it out tonight and had some initial pawl grind coming out of park (only in P and N)... R & D no grind. Finally got it to stop and cycled through all gears and no grind when driving around. Shifted fine. Shut off and started in neutral and it started up just fine (assuming since the pawl wasn't engaged)

So I started thinking it has something to do with the Lokar linkage.. perhaps not fully retracting when in park (to engage the pawl?) Here is what I did and the results:

1.) disconnected the linkage and shifted the transmission by hand. When i put it in R, then back to P, the pawl wouldn't engage until I rolled it ahead a little bit and I could then hear the 'click' of the pawl and it was locked. I started it up and no grind.

2.) once I took it out of park, put it into reverse (or any other gear), I could roll the vehicle freely.. this doesn't seem right? the transfer case is in Rear/High.. shouldn't the transmission be effectively locked when in reverse?

I'm pretty sure i'm narrowing down on it though. The pawl doesn't fully engage unless the bronco is rolled just a bit after coming out of park???? It also creates the grinding noise when going into park?? But when it's fully disengaged, no noise.

There is a possibility that the input gear of the tcase could have been installed backwards. This would give no high range on the rear axle. It would act just like it was in neutral if the levers were in rear high. You wouldn't be able to drive it though until you engaged the front axle in high range.
Would this explain why I can roll it around when the transmission is in R and the Transfer case is in Rear/High? I tested Rear/Low and I could still roll freely while in R.

I can drive around though in rear/high right now.

I'm terribly confused here... but at least I found the source of the grind.
 
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Viperwolf1

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When the engine is off, every gear in an auto is neutral except park.
 
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1buckeyefan1

1buckeyefan1

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When the engine is off, every gear in an auto is neutral except park.

Thanks, that eases my mind a bit. I appreciate your patience in helping me troubleshoot this.. it has to be tough explaining it to an elementary student in transmission basics :) You can't imagine how helpful this forum has been.. i never would have undertaken the swap without knowing you guys got my back!

So I think this takes me back to the shifter and how (any) pawl engages without the vehicle slightly rolling forward for it to 'catch'? I'm pretty sure the transmission is still spinning when i put it into park and when the pawl tries to engage, it grinds?

But i'm pretty confident if i were to:

1.) shut the vehicle off in neutral.
2.) Put it into park
3.) then roll it forward for the pawl to catch, it won't partially engage the pawl and grind.

What am i missing here? Is my Pawl (spring?) bad, or something amiss in my shifter linkage when I swapped in the Lokar kit?
 

Viperwolf1

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The trans internals won't be spinning when you put it in park unless you're trying to put it in park while you're still moving (or tcase is in neutral which we already covered).

After it's in park the wheels may have to roll a couple inches for the pawl to catch a space between the dogs on the ring. That's the way all park mechanisms work.

You may have a problem with the shifter adjustment. When you select a gear position on the shifter, you may be in between gear positions at the trans. This is a bad thing that can easily destroy a transmission. You should check this out.
 
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1buckeyefan1

1buckeyefan1

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go back and reset lokar linkage step by step, cheap check.

73AZ - I think you were on the right track.

The trans internals won't be spinning when you put it in park unless you're trying to put it in park while you're still moving (or tcase is in neutral which we already covered).

After it's in park the wheels may have to roll a couple inches for the pawl to catch a space between the dogs on the ring. That's the way all park mechanisms work.

You may have a problem with the shifter adjustment. When you select a gear position on the shifter, you may be in between gear positions at the trans. This is a bad thing that can easily destroy a transmission. You should check this out.

Viperwolf - I'm pretty sure you nailed it. I'm re-reading the Lokar instructions and am wondering what i might have done wrong. At first I panicked and thought that I might have aligned the gear selector plate wrong with the piston (ie, I thought I was in P, but the piston wasn't??).. but I think the flat part of the selector shift prevents that from happening.

I believe the piston fully compressed means that I am in park (and it also engages the pawl via the connecting rod). I believe this is correct?

4r70W in park.jpg

I'm using a Flaming River column that doesn't have any catches except for P (I'm assuming to keep it from accidently destroying the Pawl) and you can't go back past N w/out pulling the lever back. When chatting with Flaming River on the phone, they stated their column doesn't have any built-in catches and you rely on the transmission detents to put it into each gear. They feel pretty solid as I shift through.

I do remember fighting the Lokar ACA-1808 linkage when i first installed it to get the correct amount of throw as well as to *almost* line up with the Flaming River shift indicator.


Lokar recommended starting P at 7:30.. but when I got to 1, I didn't have enough travel in the rod to get it back to something like 5:00.


lokar park.png


So I ended up putting P at around 9:00


4r70w P.jpg


Then R:


4r70w R.jpg


Then N:


4r70w N.jpg


Then D:


4r70w D.jpg


Then 2:


4r70w 2.jpg


And finally 1:


4r70w 1.jpg



Which gave me the right amount of travel in both the column indicator as well as the transmission without binding. If shifts smoothly and lands on the detents.

I'm thinking in my strive to get it 'spot on' the column indicators, I may have started with P a little too far over and it now isn't fully engaging P (and not fully tripping the Pawl?)

Does the clocking position matter (that it doesn't match Lokar's suggestion) as long as the travel works and it doesn't bind? Or is this ultimately the source of my troubles?

I'll spend the next few days fine-tuning it with the pan off before I try to drive it any further. if anyone sees anything amiss, please let me know!
 

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