Hello all,
I'm new to post here but have been lurking since I bought my Ranger last fall. Well now I think it's smart to start posting; and I need some guidance before I dive into this fix.

The timeline:
About 8 months ago I started to notice she would shudder and buck around 40mph, especially uphill. Feathering the throttle down a few times would solve it for a few miles, but I immediately started checking things.
Had a misfire code, all new ignition parts. Code gone.
Had an exh. gas re-circulation code, found previous owner had deleted the EGR sensor, replaced it. Code gone.
O2 sensor code, ignored.
Transmission fluid was thick and black, overfull 1qt.
I had put about 250 miles on the truck at this point.
So I siphoned out 4qts and topped off with clean; rinse and repeat twice until it all cleared up.
She ran well and good (about 110miles) until last Friday on my hill climb into work (10-13% grade 1.4miles).
On the way up the hill it was like I had my foot on the clutch or the slave was leaking in a manual.
The only way to gain traction felt like dropping rpms. But that only slowed me down.
I let her cool for about an hour, pouring water along the outside of the tranny dip tube.

That's the last she's driven. Now I have her up on stands with enough clearance to pull the transmission but don't know how far to go, how much to invest up front and what steps I can take to diagnose the fault (before doing the whole drop).
I only need it to make the hill climb once a week, and coast back down. If I can avoid a rebuilt that would be swell.

I know many forums don't appreciate starting new threads when a topic has been covered, but in this instance I'm having trouble finding someone who had similar symptoms to me, and I worry I might've complicated things by not pulling the TQ back when it was shuddering.
Thanks for what you can offer!

 

How many miles on this 27 year old?
Electric or manual TC?

"Thick and black" fluid means neglect and overfill, ineptitude at the very least.
Still, you might have a clogged filter even with your two fluid refreshments. Did you use MerconV?
Is it weak in reverse?
Dropping the pan and changing the filter is the easiest and cheapest next thing to do.

What does, "not pulling the TQ back when it was shuddering.", mean? Backing off the gas?

 

215k on the dash.
Not sure how to tell electric or manual. Obviously it's an Auto. Is that something I can find with the VIN?

I did use MerconV
It's been weak in reverse for a while.

Not removing and replacing the Torque Converter, sorry. Not TQ.

 

The transfer case (TC) has a stick on the floor or an electric switch on the dashboard.

Going into reverse requires more fluid pressure. A weak reverse points to a failing pump or clogged filter.
You might just be a transmission filter away from joy!

 

It's electric, switch on the dash 4x4low, 4x4high and 2wd.

Does it make sense to drop the pan and do the filter+fluid first; or to drop the whole transmission and replace the converter?

I don't wanna risk wasting 11quarts of fluid, and I don't think it's wise to reuse it after it's mixed with the fluid in the converter.

 

It sounds like you know what you're doing.
If the torque converter is worn/bad, then yeah, replace it. A guy I trusted in a transmission shop, told me to never reuse a TC.
Also, I've read to make dead certain the TC is seated correctly because if you don't, you'll destroy the pump when you tighten the trannie to the engine.

 

Thanks a bunch; time to wrangle a transmission jack and get to busting knuckles.

Any tips of those exhaust header bolts? I've been soaking them in penetrating fluid for a few days. Are they studs in the block? Do they break easy?

 

Yes, they are studs in the block. I've only removed a few exhaust manifolds and had good luck.
As you, I expected them to break.

A couple of drops of penetrant every couple of hours over a couple of days is what I'd try to do.
Since you'll be turning nuts, have a propane torch ready to heat 'em up. They'll expand and ease removal.
If 'toys' are your bag, an induction heater for nuts might be fun to use. However, I have no idea how much they cost.

You can see exhaust manifold studs on the RockAuto site. If any break, consider stainless steel (through JEGS?) or OE replacements.

Best of luck