4R70w Engaging Late in 1st and Reverse - Update Problem Solved!

[Ol'Blue]

Rebuilt (myself) and have about 50 miles on it. Was working great after some adjustments to the US Shift program. Got confident and decided to give it some throttle and get it under some good load and was fine. A couple stop lights later and didn’t want to move until I got up to about 1,300 rpms (stock converter). Got home and now doing same thing in reverse.

2-3 and 3-4 seem just fine.

Fluid level reads a little high and was operating at about 180*.

Any suggestions?

 

[Ol'Blue]

Doin some googling and maybe need an adjustment to TPS. I’m carbed and maybe need to adjust to increase voltage although I’m not getting a low voltage error on the controller.

 

[DirtDonk]

Been watching this, but really had nothing to add.
Not familiar with all the little ins and outs of 4R70W tuning.
But just out of curiosity, is this the current generation of US Shift controller? Or an older one?
Any of the old transmission components that you re-used?

 

[Ol'Blue]

Been watching this, but really had nothing to add.
Not familiar with all the little ins and outs of 4R70W tuning.
But just out of curiosity, is this the current generation of US Shift controller? Or an older one?
Any of the old transmission components that you re-used?

Hey Paul !

Its the newer one US Shift Quick 4 Gen 2.
I used the Transmission Bench full rebuild kit and while rebuilding I found a few components that needed replacement. One of the clutch drums and a few other odds and ends. I can recall everything, its been a few months.

I looked at the TPS before work this morning and I think the linkage adjustment slipped so its not getting the voltage it needs. Im hoping its something that simple! Will check tonight if I have time and report back.

Thanks!

 

[DirtDonk]

I hope it’s that simple too! Wouldn’t that be nice…
Got a pic of how you mounted your TPS?
Any chance any of these new components could be defective right out of the box? Like so many are these days?
Granted, most mechanical parts are not too bad. Mostly the electromechanical once giving us fits. But it wouldn’t be the first time a clutch, or friction surface of some kind gave us trouble. Especially where two machined mating surfaces have to meet perfectly.
Think of all the brake shoes and pads that don’t fit their intended application!

 

[DirtDonk]

Oh, and speaking of which, was just watching an older episode of roadkill garage, where they were trying to put the brakes on one of their Duster projects I think.
The drums didn’t even come close to fitting. About a quarter inch too small if I remember, so they reused the old drums instead.
He commented on where it might be wrong part in the box, or wrong part number, or something. But didn’t include potentially defective manufacturing in the list.

 

[Ol'Blue]

I miss Roadkill, Roadkill Garage, Faster with Finnegan, Hot Rod Garage, Engine Masters and all the others that got cancelled. What is the world coming to?!

I used this kit on my Quadrajet. I'll try and get pics of mounting tonight.

 

[DirtDonk]

Oh man, you’re making me jealous! I always wanted to try a quadrajet. Especially when I was out, actively for wheeling often.

 

[Ol'Blue]

Oh man, you’re making me jealous! I always wanted to try a quadrajet. Especially when I was out, actively for wheeling often.

I monkied with the first Gen Sniper when it first came out for months and finally went back to the Qjet.

 

[Ol'Blue]

Well the TPS linkage didn’t slip like I thought. I did a TPS calibration and that didn’t change anything. When I took it for a test drive it won’t shift into 2nd automatically now. Only shifts into second by the column shift.

Will call US Shift and Transmission Bench tomorrow for help but if anyone out there has thoughts please share.

Here’s a couple pics of the linkage Paul.

Thanks

 

[Broncobowsher]

Con you monitor if it is calling for a shift and it isn't happening, or is it not commanding it?

 

[Ol'Blue]

It’s not calling for shift. Readout stays in 1st unless I manually shift.

 

[Ol'Blue]

I added a quart of fluid thinking I maybe had the wrong dipstick, no change.

Increased the shift firmness and now it takes off from a stop without having to gas it and get into higher RPMs. Feels normal from a take off now. So that’s good but still not shifting into second unless I do it manually.

 

[Broncobowsher]

It’s not calling for shift. Readout stays in 1st unless I manually shift.

Since it started this after a TPS adjustment, I would really be looking at that again. Maybe the MLPS? It is reading vehicle speed?
Not commanding a shift is either the computer not programmed correctly, or it is getting the wrong signals. There are only a handful of signals, TPS, MLPS, OSS.

 

[Ol'Blue]

I spoke the Kevin at US shift and he’s leaning towards having the lighter spring (blue) that controls the line pressure. I remember having to replace one of the springs during rebuild as it was broken but don’t remember what color replacement spring I used.

He also suggested I disable the RPM input since I’m not using it.

I disable it, took it for a drive and noticed the MPH on the controller was very low.

I reset the speed sensor and everything was great! It was set on year 2004 and up/24 pulse which is wrong.

Drove it for a few miles then got it home to drain off some of the extra fluid I added.

Took it for a drive and about a mile later it missed 4th and reved up.

Now I only have reverse, 1st and second and going into those gears it takes a second like it did before. The controller is calling for 3 but not engaging.

I wonder if my pick up came loose and only getting pressure when over filled.

So stumped

 

[bigmuddy]

Jeez man, I hope you get this figured out.

I hope to finally get my rig back on the street after a crazy long hiatus and am running the 4R70w and controller.
This is not giving me a warm fuzzy!

 

[Broncobowsher]

If you get a call for 3rd, and it stays in 2nd. Thena call for 4th neutrals out. You lost the direct clutch. Doubt it is the clutch specificly, but the hub can split open or the stub shaft can twist off. Did that once on a Ranger. Hard shift into 3rd and it had enough grip that the weak point was the stub shaft. Usually it is the hub splits open.

 

[Ol'Blue]

If you get a call for 3rd, and it stays in 2nd. Thena call for 4th neutrals out. You lost the direct clutch. Doubt it is the clutch specificly, but the hub can split open or the stub shaft can twist off. Did that once on a Ranger. Hard shift into 3rd and it had enough grip that the weak point was the stub shaft. Usually it is the hub splits open.

Well that would suck. Any chance it could be low pressure? Or is there anything else I can check. I’m about at the end of my capabilities on this and may have to take it to a shop.

 

[Broncobowsher]

Put a pressure gauge on the direct clutch port and see if you get a pressure rise when 3rd is commanded. No rise, something in the valve body. Rise, without gear engagement, hard parts issue.

Considering I have not had one of these in 15 years, it is amazing I still know so much about them,

 

[Ol'Blue]

Put a pressure gauge on the direct clutch port and see if you get a pressure rise when 3rd is commanded. No rise, something in the valve body. Rise, without gear engagement, hard parts issue.

Considering I have not had one of these in 15 years, it is amazing I still know so much about them,

And always thank you for your valuable info Broncobowsher. You’ve helped me more than a few times over the years.