Ranger reverse

[Healing Hawk]

I bought a 90 Ranger XLT Ext cab 4X4 4.0L pushrod motor A4LD automatic (maybe - info on this site may say it is) that I really like (I also have a 2001 Ranger regular cab XL 2.3L that won't make enough vacuum to run the brakes (really fun to drive, so I don't) that, at 230,000 miles has 2500 rpm of tach left at 100mph without scaring me - I need a track to go faster than that. R90 only has 85 mph on the speedometer and it does that easily but there's a clunk in the front axle I don't want to diagnose.
Anyway, R90 has reverse, but only when it wants, but it's so seldom I can safely say it doesn't have reverse, but, about 3 weeks ago, I needed reverse, didn't have it so I stuck one leg out the door and pushed it backward with my leg. Reverse decided to work, threw me out enough to smack me to the pavement with the door and run over me. I don't recommend this. I'm fairly anxious to fix this, but automatic transmissions haven't been a problem until now. I changed the ATF, filter, pan (with a drain plug) and gasket (in my gravel driveway, not jacked up - that much laziness is no virtue) and poured 16 oz. of Marvel Mystery Oil in it then filled it. I discovered it has a fairly large transmission cooler just behind the grill, so I poured more ATF in, to the place it said not to put in anymore. It went into reverse and let me drive around the driveway in reverse. I went to D, pulled back to the work space, tried reverse and it shot me a middle finger, hadn't engaged until shortly before it ran over me. Does it have a reverse solenoid? Something on the linkage? I hope this isn't something that has only happened to me. Has anyone fixed that? Thanks. I was born handing wrenches to my dad, who was under his latest hot rod in the early 50's (I'm old) and my first impulse is to tear it apart and find what's broken. It usually works. It's hard to ask for help, but please help me if you can.

 

[lil_Blue_Ford]

So, I’m assuming all forward gears work ok, or does it not have first?

When you had the pan down, the reverse servo thing is in there. Two O-rings and a gasket, IIRC. Usually the O-rings and/or gasket is bad. If you don’t have 1st, it potentially could be a problem with the band (reverse and first use the same drive band), but it might also be the O-rings or gasket. Last time I had one apart, I went pretty much full bore with a shift kit and valve body mods, then adjusted the bands as best I could (rust was a problem). I’d start along those lines…

 

[RonD]

Welcome to TRS

A4LD's, like pretty much all automatics, only use solenoids for changing forward gears as speed increases or decreases, i.e. 2, 3, and 4
1990 A4LD only had 2 solenoids, one for torque converter and one for 3 to 4 shift

1st or Reverse are mechanical engagements, using the shifter

But to engage any "gear" in an automatic there must be high enough fluid pressure, thats what the ATF is used for, it lubes and cools of course but also holds clutches engaged or disengaged and bands(brakes) engaged or disengaged using fluid pressure
80-100psi is required for forward gears
140-160psi for Reverse

If there are any internal leaks in gaskets or seals then pressure goes down and Reverse is lost first because it requires the highest pressure

The ATF pump spins at engine RPMs as its driven by the torque converters outer case
The Valve Body routes the pressure from the pump thru passages to the clutches and bands, to engage and disengage gears
Valve body is usually where pressure is lost from blown gaskets or seals
But its not always a pressure issue, there are one-way clutches(sprags) that can fail
But for sure not solenoids if Reverse is intermittent, on any automatic

At 230k known miles a full rebuild wouldn't be out of line, the clutches, bands and pump should all be changed

 

[Josh B]

Good luck with it Hawk, welcome to TRS

 

[Healing Hawk]

So, I’m assuming all forward gears work ok, or does it not have first?

When you had the pan down, the reverse servo thing is in there. Two O-rings and a gasket, IIRC. Usually the O-rings and/or gasket is bad. If you don’t have 1st, it potentially could be a problem with the band (reverse and first use the same drive band), but it might also be the O-rings or gasket. Last time I had one apart, I went pretty much full bore with a shift kit and valve body mods, then adjusted the bands as best I could (rust was a problem). I’d start along those lines…

It has first, and shifts good all the way to 4th. T the things you mention here sound like a good idea for a truck that's going to do some real dumb stuff I'm unfortunately not too old for. It already has a crumpled fender/door, for authenticy. Most of the mud from the crumple is still in the cab, especially in the seat. If I get middle class (I do, now an then), I'll take my pressure washer to it, if we ever get out of this drought so I can use water outside without risking jail time. Authenticity's pretty cool.. I think I'll learn to rebuild the front axle from the steering and down till I find all the damage.. I didn't pull down the valve body, but saw it, and thought it looked difficult. How do you change shift points in the ECM? What you've told me is what's going to fix it. Is there a manual? Getting another transmission (after I do what you say and it does what you say, so it doesn't get another chance to kill me - by that tactic, anyway). I spent a year in Vietnam when I was a legitimate kid and nothing (well, one thing) over there was as terrifying as watching the driver side front tire with a 2-ton truck atop it coming at me and I couldn't move after smacking pavement with my head, but I somehow used my left leg to shield my right one, and maybe I should smack my head on pavement more often when I'm in the binds I get into. My right leg is good. I want the shift kit and valve body mods. Where do I get parts? Is there a manual? You're kidding about the rust, aren't you? What is "IIRC?" Sometimes I'm dumb as nails.

Good luck with it Hawk, welcome to TRS
Thanks, Josh B., for the welcome and the info. I thought Rangers were "keep the fluids clean and full and drive it forever". I had a 66 Ford Supervan with a 240 that drove 400,000 miles then sold. After I got some weight over the back wheels, it wasn't too scary to drive too fast. Neither of my Rangers beat that van, and it was lots better to sleep in. I have to replace the front oil seal on R90 and maybe a valve job on the 2.3L in R01. I like doing that stuff.

Welcome to TRS

A4LD's, like pretty much all automatics, only use solenoids for changing forward gears as speed increases or decreases, i.e. 2, 3, and 4
1990 A4LD only had 2 solenoids, one for torque converter and one for 3 to 4 shift

1st or Reverse are mechanical engagements, using the shifter

But to engage any "gear" in an automatic there must be high enough fluid pressure, thats what the ATF is used for, it lubes and cools of course but also holds clutches engaged or disengaged and bands(brakes) engaged or disengaged using fluid pressure
80-100psi is required for forward gears
140-160psi for Reverse

If there are any internal leaks in gaskets or seals then pressure goes down and Reverse is lost first because it requires the highest pressure

The ATF pump spins at engine RPMs as its driven by the torque converters outer case
The Valve Body routes the pressure from the pump thru passages to the clutches and bands, to engage and disengage gears
Valve body is usually where pressure is lost from blown gaskets or seals
But its not always a pressure issue, there are one-way clutches(sprags) that can fail
But for sure not solenoids if Reverse is intermittent, on any automatic

At 230k known miles a full rebuild wouldn't be out of line, the clutches, bands and pump should all be changed

Wow! Is there a manual you recommend? I'm one of those weird people who learn stuff by reading about it first then doing it. It sounds like a rebuild. At the tri I'll never have to do it again.parts house, a rebuilt is $2K for a cheap one. A rebuild kit is $170 on ebay. Can the pump be rebuilt, or you just buy a new one? The second approach makes too much sense to actually do it. Thank you. I can tell my garage is going to be converted back into the garage. It's nothing like the videos I see rescued wrecks pushed into, but I don't have a podcast, either. Thanks again. This was the right place to ask.

 

[Healing Hawk]

Good luck with it Hawk, welcome to TRS

Good luck with it Hawk, welcome to TRS

Thanks. Twice and knowing is my philosophy, too.

 

[lil_Blue_Ford]

It has first, and shifts good all the way to 4th. T the things you mention here sound like a good idea for a truck that's going to do some real dumb stuff I'm unfortunately not too old for. It already has a crumpled fender/door, for authenticy. Most of the mud from the crumple is still in the cab, especially in the seat. If I get middle class (I do, now an then), I'll take my pressure washer to it, if we ever get out of this drought so I can use water outside without risking jail time. Authenticity's pretty cool.. I think I'll learn to rebuild the front axle from the steering and down till I find all the damage.. I didn't pull down the valve body, but saw it, and thought it looked difficult. How do you change shift points in the ECM? What you've told me is what's going to fix it. Is there a manual? Getting another transmission (after I do what you say and it does what you say, so it doesn't get another chance to kill me - by that tactic, anyway). I spent a year in Vietnam when I was a legitimate kid and nothing (well, one thing) over there was as terrifying as watching the driver side front tire with a 2-ton truck atop it coming at me and I couldn't move after smacking pavement with my head, but I somehow used my left leg to shield my right one, and maybe I should smack my head on pavement more often when I'm in the binds I get into. My right leg is good. I want the shift kit and valve body mods. Where do I get parts? Is there a manual? You're kidding about the rust, aren't you? What is "IIRC?" Sometimes I'm dumb as nails.

Ok, so I didn’t specifically mention it, but what I recommended covers a lot of what @RonD was talking about. Valve body and such is messy and tedious, but not at all difficult. Lots and lots of bolts that have to be tightened in sequence with a torque wrench and you have to be really careful not to scratch anything. It’s all aluminum and I used as much plastic and wood tools as possible when doing the shift kit and stuff. Shift points in the A4LD are all controlled by the valve body, the computer only has control over torque converter lockup and the 3-4 shift. Everything else is done by pressure and valving.

I went pretty much whole hog on it. I did some video and was going to do a write-up but never got done with it yet. I’m working on it. The difference was huge, I went from a sluggish reverse engagement and mushy shifts to snappy crisp shifts and hitting the loud pedal too had would break the back tires free (4.0 OHV Ranger with factory limited slip). I’d gladly do it again and I’d probably go all out and do the max of everything (couple holes I went small on because I didn’t have the exact drill but needed, doing it again I’d buy the like 3 bits needed to max out things). The Transgo shift kit came with some decent instructions and the rest of the information I used I found over on the Explorer forums.

A4LD Valve Body Rebuild Diary

Well I'm back. When I did the A4LD rebuild diary I rather shorted the Valve body rebuild portion. Tn Explorer did a great writeup and kind of filled in the void there, but I wanted to add one of my own. In this thread I will compare valve body rebuild kits (sometimes referred to as shift kits...

www.explorerforum.com

Rust, is unfortunately a way of life in the north here. It’s ridiculous.

IIRC = If I Recall/Remember Correctly