Transmission ID and can I swap?

Got a bit of a head scratcher here. I've been around long enough to know to check the tech library. I did, it didn't help.

1999 Ford Ranger XLT Extended Cab 4x4 W/ 4.0L Auto and factory tow package.

According to the chart in the tech library my truck should have a 5R55E due to being a "1998-2011 4.0L Ranger". Per the chart in the tech library my door sticker would agree with this as it has "D" for transmission code.

Several years ago I had the transmission rebuild by a very good, very experienced local shop. When I got the truck back and looked at the receipt it had 4R55E on the receipt. I asked at the time because even then I thought it had the 5R transmission, but they assured me that it was definitely a 4R trans. Those guys are good at what they do and it was working good so I thought no more about it.

The same transmission ID article also shows the bolt pattern for the transmission pans. I was just under the truck an hour ago for some other work and the pan definitely has 18 bolts as shown for the 4R transmission.

What's going on with my truck? Could someone have swapped in a 4R55E in the past and it still function right "missing a gear"?

Is the tech library wrong about pan bolts and 5R55E have same pan as the 4R55E? (<< my guess) Is it wrong about trans code and they were still installing the 4R in 99 (06/99 build date)?

If it is a 5R55E and trans shop rebuilt it as a 4R55E, would/could that cause any issues that aren't throwing a code? I never drove the truck when it was new and it was rebuilt due to wear and slipping. As I found out not long after buying it, the previous sucked at maintaining it, so I didn't really have a good baseline to compare before and after rebuild. Closest I can get is my dad's '02 4.0L 4x4, it always had a firmer shift, but it's also newer with a different engine and different tuning.


On similar note if my truck did somehow come with a 4R in '99, would it be possible to swap in a 5R and have it work right?

I'll probably be installing a new engine next year (please don't ask) so it would be the ideal time to swap in the correct transmission or upgrade to a better one.

Thanks!

What trans code is on the door tag? T is 4R, D is 5R
Obviously that only tells you how it started though.

"D" code

It was in the first post:

JoshT said:

1999 Ford Ranger XLT Extended Cab 4x4 W/ 4.0L Auto and factory tow package.

According to the chart in the tech library my truck should have a 5R55E due to being a "1998-2011 4.0L Ranger". Per the chart in the tech library my door sticker would agree with this as it has "D" for transmission code.

Click to expand...

Door code says 5R. Chart says 5R.

Pan bolt pattern says 4R. Transmission shop said 4R.

I guess I'm looking for any other indicators that would say for sure that this is a 4R or a 5R. Also if it is a 5R did the transmission shop mess up anything by rebuilding it as a 4R?

Crap. Sorry, I was doing two things at once and not paying enough attention.

The internal differences between the 4R and 5R are very minimal. The fun part of automatic transmissions is that you can add gears just by changing when, what, and how many things inside the trans are applied. Which means you can possibly turn a 4 speed auto into a 5 speed just by changing the software.

The trans you have is correct for the computer, of you would have lights and confusion aplenty.

what he said. the 5R55E is basically the same as 4R55E. if you examine the gear ratios you can see where engaging overdrive while in 1st gives you the "new" 2nd gear in between the old 1st and 2nd. that's done with the electronics/software.

pjtoledo said:

what he said. the 5R55E is basically the same as 4R55E. if you examine the gear ratios you can see where engaging overdrive while in 1st gives you the "new" 2nd gear in between the old 1st and 2nd. that's done with the electronics/software.

Click to expand...

Yeah, with just a simple planetary you can make 6 gears, including reverse overdrive. IIRC the 4R/5R series has two, so it is easy to make extra gears just by adding extra shift points.

adsm08 said:

Yeah, with just a simple planetary you can make 6 gears, including reverse overdrive. IIRC the 4R/5R series has two, so it is easy to make extra gears just by adding extra shift points.

Click to expand...

Well that's interesting.

How about an extra-high overdrive and super low granny gear sub-1st?