85 A4LD and duraspark

[ford4wd08]

@RonD @19Walt93 @RobbieD @Transman304

Any ideas as to why this thing will not upshift?

 

[heisler0]

@RonD @19Walt93 @RobbieD @Transman304

Any ideas as to why this thing will not upshift?

I am having same problem. Just rebuilt the motor and did this conversion with similar results stay in 1st gear and will not upshift. if you put in 2nd gear it goes into 2nd and reverse works fine.

 

[19Walt93]

Applying vacuum to the modulator wouldn't cause an upshift. I'd look hard at the governor if they thoroughly went through the valve body and checked EVERY valve for free movement. I suspect there's a particle of aluminum causing a valve or the governor to stick.

 

[ford4wd08]

Applying vacuum to the modulator wouldn't cause an upshift. I'd look hard at the governor if they thoroughly went through the valve body and checked EVERY valve for free movement. I suspect there's a particle of aluminum causing a valve or the governor to stick.

They told me the governor was spotless. I think it is in the valve body. They had it off, and said it was ok, but I'm suspicious.

 

[ford4wd08]

Applying vacuum to the modulator wouldn't cause an upshift. I'd look hard at the governor if they thoroughly went through the valve body and checked EVERY valve for free movement. I suspect there's a particle of aluminum causing a valve or the governor to stick.

Circling back to this.... So the governor and the modulator work together to cause the 1 - 2 shift correct?

You said applying vacuum won't cause and upshift, is the modulator more about the timing of the shift depending on engine load?

 

[RobbieD]

Sorry to hear that you're still having trouble. I don't know squat about transmission internals, but I can look up and post stuff out of the manuals (troubleshooting guide steps may help your trans guys). You have reverse and first in "1", but no 1-2 upshift and no third at all, right? Bear with me; I have errands to run this morning, but can I try to post some manual pages later.
Before I ditched the A4LD in my B2, mine wouldn't upshift one time, but cleaning the governor took care of it.

 

[ford4wd08]

Sorry to hear that you're still having trouble. I don't know squat about transmission internals, but I can look up and post stuff out of the manuals (troubleshooting guide steps may help your trans guys). You have reverse and first in "1", but no 1-2 upshift and no third at all, right? Bear with me; I have errands to run this morning, but can I try to post some manual pages later.
Before I ditched the A4LD in my B2, mine wouldn't upshift one time, but cleaning the governor took care of it.

Yes, I have reverse and 1st.

It will not up shift to 2, and last time I drove it, I could not get it into 3rd.

I was able to manually put it in 2nd with no issue.

To me that seemed to be valve body or governor related.

No rush, I appreciate any input!

In a weird way, it makes me feel like a decent mechanic, lol. I can have a conversation with them about what is going on and where I would look.

 

[19Walt93]

The governor spins on the output shaft and provides the speed"information", the modulator uses vacuum to determine how much load is on the engine, and the TV rod causes the forced downshift on sudden acceleration. There are accumulators in the valve body that cushion the pressure to make shifts less harsh and if they stick can cause pressure loss and slippage. I'd look hard at the governor and maybe try another shop, they sound like they're lost.

 

[ford4wd08]

The governor spins on the output shaft and provides the speed"information", the modulator uses vacuum to determine how much load is on the engine, and the TV rod causes the forced downshift on sudden acceleration. There are accumulators in the valve body that cushion the pressure to make shifts less harsh and if they stick can cause pressure loss and slippage. I'd look hard at the governor and maybe try another shop, they sound like they're lost.

Only trouble with another shop is I am unwilling to pay them anything unless it is fixed. They've already dropped it and replaced some parts. And they provided the tow to the shop.

I think they are disorganized, but they have good reviews..... Just have to see.

 

[19Walt93]

Only trouble with another shop is I am unwilling to pay them anything unless it is fixed. They've already dropped it and replaced some parts. And they provided the tow to the shop.

I think they are disorganized, but they have good reviews..... Just have to see.

They may very well be a good transmission shop but they probably have at least one tech younger than the truck. I think I'm a pretty good mechanic but rebuilding the chassis on my friends 35 pickup was an eye opener.

 

[ford4wd08]

They may very well be a good transmission shop but they probably have at least one tech younger than the truck. I think I'm a pretty good mechanic but rebuilding the chassis on my friends 35 pickup was an eye opener.

They did rebuild an Aerostar A4LD early this year as a refresher!

You're right, but a few were around during the A4LD days.... It is 35 years old, so I give them credit for taking it on lol.

 

[RobbieD]

See if these are any help. All from the Ford 1985-86 Ranger / Bronco II Truck Shop Manual. First, diagnosis steps for "No 1-2 upshift", then two following pages showing small parts, and valve assignment in the valve body. I'll dig out more as time permits, and also ask the trans shop if there's anything specific that would help them. I don't know what tech resources they have access to, and as pointed out these transmissions are now antiques, and a lot of shops won't even work on them.

 

[19Walt93]

It just occurred to me that we had problems with the shuttle balls wearing down and passing through the holes in the valve body in C3 transmissions. The A4LD, 4r44, and 5r55 are all descended from the C3. If any of the balls are worn undersized it would cause problems.

 

[heisler0]

So i ended up getting a used transmission disassembling drilling hole for pressure switch then reassembling. Then swapped with transmission in truck. I pulled trans apart(original) to inspect and it had shavings in pan from drilling hole so probably in valve body also.

 

[ford4wd08]

Update for August so far.....

Still no Bronco II at the house yet. They have had it over 2 months. Apparently I am not their priority and when it comes time to ask me for money, I won't be paying prime prices......

Last update I got when I called Friday is that they had a new case from another built and swapped it all out. Then it was functioning properly on a test drive, then it stopped working again.

They said they notice a big leak and figured out the modulator was dumping fluid. They said they think they got a new bad modulator and are going to replace it out.

What a fiasco.....