1984 F150 C6 Question

I'm on the fence as to whether I want to rebuild my C6 or buy one already done. I was looking at the O'Reilly website and they list two C6s based on the transmission id on the trans tag. Big surprise, there's no tag on my trans. Question is this, what's the difference? Why two? Only things I can think of is tail housing length or spline count on the output.

Oh, truck is a RWD supercab with a 351.

I've emailed the company that builds the transmission for O'Reilly's but no answer yet.

Any help would be appreciated.

I should mention that there's a third option I'm considering which is putting a 4R70W from a V6 Mustang in it with a stand alone controller.

Yes, I see the two different C6 transmissions on this page.  Part #: A117501 does Tag ID: PGD-DL13, PGD-DL15, PGD-EY, PGD-EY3, PGD-FK, PGD-FT.  And Part #: A117039 does Tag ID: PGD-DP, PGD-DP1, PGD-DP3, PGD-DP13, PGD-DP14, PGD-DS, PGD-DW, PGD-DW10, PGD-DW11, PGD-EP, PGD-EP1, PGD-ES, PGD-EW, PGD-FA.

If you look on our page at Documentation/Driveline/Transmissions/Automatic Transmissions/Transmission Applications and then the Applications tab you can scroll down to 1984 and see the possible tag ID's.  I've included part of that below.  And from that I see PGD-DK13; PGD-DL14; PGD-DW11; PGD-EV; & PGD-EW.

And from that list it looks to me like the only matches are PGD-DW11 & PGD-EW, and both of those are with Part #: A117039.  That really doesn't give a whole lot of warm fuzzy feelings, but if I were buying one of those two I'd go with that one.  Hopefully the rebuilder will be able to answer your question more definitively.

Thanks for that info. I just wish there was something that showed the difference that I could physically put eyes on and verify. When or if I hear back from the remanufacturer, I will definitely post it here.

I work at a transmission shop and I would highly recommend having a shop rebuild it rather than ordering a reman. It’s typically cheaper and if you have an issue it is much easier to deal with a transmission shop face to face. So if there’s a reputable shop around you I would have them do it.

As far as the differences in the transmissions it could be several different things - converter stall, clutch count, valve body differences, pump differences, shift timing, vacuum modulator, etc. Maybe the trans specs changed if you got certain packages like a snow plow package or different motors like an HO 351w or the 2bbl 351w? I’m just spitballing but it wouldn’t surprise me.

If you decide to go the reman route you need to replace the radiator/cooler and blow the cooler lines out with solvent. Otherwise you might send metal and other materials back into the new trans from the old cooler.

I forgot about the mention of a 4r70w. They’re good transmissions. We do see them on a semi regular basis but they’re getting to age where they’re just worn out. They’ll be more expensive but depending on how much you drive, your current final drive ratio, and your typical cruising speed, it could pay for itself.

Thanks for the info Jacob! I think I've pretty much decided to rebuild the C6 if I keep it. I've got a local shop that I've used a couple of times. They rebuilt the 4R70W in my 2000 Grand Marquis a couple of years ago and it's been solid. This truck is gonna see it's fair share of 75-80 mph on the highway which is why I was looking at the 4R70W. If it was a manual truck, I'd probably even consider doing a T5 swap in it.

Glad I could help. Spending that much time at freeway speeds I definitely think an OD swap would be good. I’ve got a very similar setup as yours, 95 351 roller, C6, 3.50 geared 9 inch. I’ve got 33 inch tires at the moment and at 70 I’m around 2700 rpm. That averages about 12 mpg. That’s also with efi and a very mild cam. But I can count on one hand the amount of times I’m on the interstate in a year so the C6 doesn’t bother me.

If you’re just gonna cruise it and not gonna try and make tons of power the 4r70w would do you well. If you’re gonna tow heavy and really work the truck hard an E4OD wouldn’t be bad either. You can build a 4r70w tough but I’ve never felt bad about having the “tougher” transmission. I’m not saying they’re weak, they live behind plenty of 5.4s that are in crew cab trucks, but there’s tougher options. Both will require a controller since they are electronically controlled. Those run about $600 with a wiring harness and you’ll most likely need to modify the driveshaft and add a speed sensor somehow. With gas prices the way they are it won’t take long to get your money’s worth out of it.

OldBlue80 wrote

I should mention that there's a third option I'm considering which is putting a 4R70W from a V6 Mustang in it with a stand alone controller.

 
I'm doing about the same thing with my 81, swapping in an E4OD with a standalone controller. I'm not familiar with the 4R70W and how dis-similar it is to the C6, but there are a lot of hidden gotchas with this type of swap, I'm discovering. Not that I wouldn't do it again, but project scope can quickly creep on this kind of thing.

Some things to consider:

- You will most likely need your driveshaft shortened
- The standalone controller may need inputs you don't currently have, such as TPS and VSS
- You might need to fabricate shift linkage
- Exhaust interference?
- New trans cooler lines if the ports on the new trans don't match the C6

You can control costs if you do the rebuild yourself. I was on the fence about it, since whatever the heck goes on in a slushbox is pure voodoo. But I watched some rebuild videos, found some really good ones, and dove in. The jury's still out on how well I did, since I'm still working through things like in the list above. But my point is, once I got in there, it was not that intimidating. I've rebuilt motors before, but never a trans, and I didn't find the trans rebuild that much more difficult than a motor rebuild. Something to consider.

X2 There’s a lot of things you won’t see coming that will add cost to the swap. That’s exactly why I have an E4OD sitting on the shop bench at home and not in my truck. I can’t decide if the swap would be worth the headaches and the extra money. Basically waiting for the right person to sell it to or finding a good reason to put it in. I’ve worked on a couple of transmission conversions at the shop and the little details add up quickly.

But if you really want to do it then do it, I think it’s a pretty cool thing to do if it’s done right. I say all that but I’m also the same person that would swap a 6R80 in my truck if I found one for dirt cheap there’s just two sides to everything

While it would be cool, that 6R80 swap gets expensive fast. The cheapest adapter I've found to mount one to a SBF was over a grand.

I believe I found an adapter for around $600 if I remember correctly. And a controller would be pushing the $800 to $1,000 mark. If I had to buy everything to do the swap it wouldn’t be worth it, or at least a 5.0 or 3.5 ecoboost would need to be attached to it. But having a transmission shop at my disposal and knowing a local machinist it would be a fun project if I had the time. I saw on a different forum where one guy put a ZF 8 speed behind an LS in a Chevelle and built his own little controller for it. Thought it would be real neat to do something like that with a 6R80