86 F250 C6 is out. Need advice, rebuild tranny for same price as Zf5 conversion

[opusd2]

Hey everyone. I have a question. I could do things the easy way and just drop the tranny (or drop off the truck) at the local rebuilder who builds transmissions for pulling trucks and off road racers and have a C6 that would probably outlast me.

Or for $750 I could drive 3 hours and get all the fixings to convert to a ZF5 transmission. It will come with a package including both drive shafts, clutch cylinder and slave, pedals, flywheel, clutch and transfer case. All (I think) from an 1990 truck.

And then there is the 4 speed route. I have a 4 speed housing and can just buy the flywheel and clutch, have the pedals, just need clutch cylinder and slave, have the tranny and 205 transfer case on a 77 highboy I could rob (along with the HD44 Axle).

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Ok, I've been rattling around the options for a while. If I do the C6 it's the least amount of work, is OVERbuilt with a low torque converter with bearings in and not thrust washers (just a really good quality one) and a very heavy duty build that even for $1200 he'd do all the work in and out for me. I am so tempted to go that way, but I was raised on manual trannys and like the idea of overdrive. It's a small drive to get the 5 speed, but on the way I found someone who would but some parts from me that would essentially just be the cost of the fuel for the drive. Which I know is a good deal.

Plus I could sell the 4 speed bellhousing because I know they are hard to come by, and I am sure I can get what I paid for it. I don't know, does anyone want a 4 speed bell housing?

Or is the idea of having a remote transfer case NP205 VS the 1356 (I think?) on the 5 speed a better solution? I know I am tempted to just keep the highboy running as is. I guess I'm just stuck. It would be an easier decision if I had a heated shop to work in, but I don't. That alone sends me to spend my money on the rebuild with upgrades by the tranny pro. If you've heard of the Crandon, WI truck races, he does a lot of building for a lot of trucks. So I have the most trust in him.

So, anyone have any other options or good advice for me? I don't mind doing the work adapting, even if it's colder out because I could through the bullet heater on me. I'm just trying to figure out what people would think would be a better option since the truck will be used for towing, I have 4.10s in it currently, have 305/70-16s on the wheels and may go to a 35"or 37" in the future (but that's not now, thats the future) or even do 3.55s.

Any opinions are greatly appreciated.

And would be willing to sell whatever I don't use. By the way, I am running my 89 GMC K1500 4x4 with 368K miles on it. I want my Ford

 

[02x72]

Not sure if it helps, or where in WI you are, but if you want to drive to Des Moines I have a good C6 you could have for free. Its going to scrap soon since its just taking up space.

 

[franklin2]

If you do not mind shifting gears and probably spending $500 + on a flywheel conversion kit, I would definitely go with the 5 speed. I had a perfectly good rebuilt c6 in mine when I bought it, and drove it for several years that way. The way my truck is setup, it would not get over 12 mpg. As soon as I swapped in the 5 speed, mileage jumped to 15mpg.

But more than that, I can now cruise down the highway at 70mph +, and not feel like the engine is going to come out of it, and you can actually listen to the radio. It has to be less wear on the engine.

Another bonus that I didn't plan on, was all the useful torque these engines have that is wasted with a automatic. The c6 and the E4OD do the same thing, you have to rev the engine high before it even moves the truck. These engines have lots of low end pull that you never know about till you get a manual tranny. What made me realize this is my driveway.

My driveway is very steep, and is gravel with a turn right at the bottom. It's very difficult to climb with a empty pickup of any type. With the c6 I had to keep my foot in it and keep the revs high, and as I would start climbing the truck's speed would start slowing. If it came close to a stop you have to start over, it will just spin in the gravels. With the 5 speed I put it in 1st, hold my foot steady on the throttle, and it climbs right up with authority, no high rpms, no slowing, just a steady pull from the engine.

The 5 speed is also very handy to hold loads back when descending mountains and such. It controls the load much better than the c6 can and saves your brakes.

 

[IDIoit]

i just converted my 87 CC LB from a T-19 to a ZF5.
one of the best things i did to this truck.
i spnt over 750 on a flywheel, pressure plate and clutch disk.
another 100 on a master & slave, not to mention the 250 i scored the F450 ZF5 for (at a deal)

if you can get all that, and the pedals... id say go that route for sure!
sure, you gotta drill the firewall for the master, but thats pretty damn easy!
what gears are in the axles?

FYI, i put my T-19 on CL trying to score some of my money back, all i got was 2 callers looking for the bell housing.
i wouldnt part it out.

 

[franklin2]

sure, you gotta drill the firewall for the master,

I didn't even have to do that. My 89 had the hole already with a little cover plate on it. Take the plate off, and the master went right on. I pulled the seat out, rolled the carpet back, and took my c6 floor cover out and bolted in the zf floor plate also. Hint; Do the cover plate first, it makes it really easy to get to the top bellhousing bolts.

Taking the seat out also makes it much easier to lay in the cab and swap out the pedal assembly. The only aggravating part about the pedals was the speedo cable. It ran right though the hole in the pedal bracket, so I had to tear the cluster out and disconnect the speedo cable from the speedo so I could fish the cable through the pedal bracket hole.

I also unplugged the harness under the brake booster and took the c6 tranny/transfer case harness out. Got the short wiring harness for the zf, plugged it in the same spot, everything plugged in, no wiring or jumpers to make at all.

 

[opusd2]

So it shouldn't be that difficult to do, is what you're saying. I've never balked at doing work, especially customizing a vehicle on my own, the only ***** (and maybe that's why things worked to my advantage) is that the expense is lower and opportunity is higher since the weather got so damn cold out. I've crawled in snow my entire life working on things having grown up on a farm and sometimes I think I'm stupid for still doing it, but I do know I can. I'm trying to see if a buddy will allow me to use his garage to do the work at his place and I'll just figure out a way to heat the area without adding so much CO that I get sick after a days work.

In my older age, I've always been one to admire the simpler way of doing things. Whether it is just going oem, this case going with the C6, or having someone else do it because of an increasing amount of arthritis developing over the years because I've worked my ass off outside in all weather both on the farm and in my full time and concurrent professions as HVAC and truck driver. I'll admit that I do like not having to do a lot of shifting in city driving, but I also like the control of the power in the truck. I grew up learning to driving truck in an old 71 Chevy with a 4 speed, my first truck (still have) is a 73 F100 with 360 4x4 4 speed and bigger tires, so I learned to feather the clutch very early on without burning things up. Plus! There was always that awesome ability to jump start the vehicle. Hell, if I could put a cable on the IP stop, I would be in heaven. But that's another goal for later on...

I have 4.10s in the pumpkins on the truck, but have the chance to swap in a set of 3.55s from a brother in law's 86 gasser. It even has a traction aid in the rear end. The only reason he parked it was because he started driving my sister's 93 Dodge Cummins 4x4 with 5 speed when they got married. Lucky sonufabitch...... Anyway, so that's a consideration since the rear may be faulty to begin with even though the brakes are new. Different thread. But the traction aid would be nice, though I think it's the trac lock which is better than open, but not as nice as a detroit but that's a future dream. And with the combo of 4.10s, the 305-70-16s and everything, the speedo is nuts on. I'm hoping that with whatever I do I can achieve that again, but if not I am not worried since I was always been able to compensate in my head for the old 73 and 33's. And as long as I can keep the cruise working, even easier. And I'm thinking that the next set of tires may be a smidge bigger, at least better in off road situations. That's another plus of a manual, being able to walk out of icy situations better, less spinning.

I've always been a huge fan of using the engine as a brake, I learned it driving truck and even incorporate it when driving my dad's 89 F150 with I6 and 4 speed. It's a torquey little motor and acts like a diesel with how it just pulls out of little situations, but it definitely saves on brakes. An auto will do the same just not to the extent that a stick will do. And if the truck pulls better, how can I not do this?

Well, looks like I will be selling that 4 speed bellhousing after all, as well as a few other things. Then all it will cost me is the fuel to go the parts, the labor, and probably clutch and flywheel surfacing if solid mass. If not, a solid mass fly wheel.

I'm just look for as many opinions as possible because cash is so damn tight right now. The cheapest and fastest would be to just rebuild the C6, and I'd know I would have a tranny that I could pull silos down with or race with. And even with the Hi-Po TC and valve body job with warranty I'd still be looking at under a grand. Unfortunately that has to be a factor too. But in this neck of the woods, just trying to find a diesel 5 speed is nowhere near under a grand, and that's just the tranny, you're lucky with a shifter too at that price.

Ugh,,, I hate this choice

And if I had the cash, I would love to take a ride out to Des Moines, it would be a nice ride. But for that, I could almost just build the tranny. But thanks tho, that's great you offered, thanks Man

 

[franklin2]

I wanted overdrive for my truck, the c6 was working perfectly. The choices seemed to be a E4OD, a ZF, or a aftermarket used add-on overdrive. I found the cheapest to be the zf. I looked also, and could not seem to find one less than $750 for the tranny. And then you add up all the other little things, and it seemed all the options were going to be at least $1500-$2000, if you figure rebuilding the E4OD, and getting the computer to run it.

I then ran across a wrecked 89 f250 with a zf in it. They wanted $1000 for it, it looked terrible in the pictures. But after a little figuring, for $1000 I would be in the ballpark of buying all the zf parts from the junkyard. I am glad I did it, because I had all the parts I needed for the swap from the donor pickup. And then I sold the Alcoa wheels that were on it, the old c6, the transfer case out of the donor, and a couple other things off the truck, and my total investment kept going down and down.

The only thing that blind-sided me was the flywheel. I didn't have a clue it had that weird DMF setup in it till I took it apart. I panicked when I saw they wanted close to $1000 for just the flywheel. And they wanted around $700 for the conversion kit. I then stumbled on to this site and they had a article about taking the old flywheel apart, drilling some holes and bolting back together solid. That's what I did, and it's been working fine now for about 5 or 6 years.

P.S. I forgot to mention, you will need to make a decision about the steering column if you go the 5 speed route. If you get a donor you can swap the whole column out, or you can do what I did, take the shifter lever off the old column, and then go out under the hood and tie the lever up coming out of the column with a piece of wire. I think I just took a piece of wire and wrapped it through the lever hole, and then wrapped it around the clutch master. If you don't do this, the lever will fall down and the column will not let you start the truck. It thinks the auto tranny is in gear and won't let the key turn.

 

[Sycostang67]

I vote for the 5spd as well. I did the C6 to 5spd swap years ago on a 460 powered F-250. One hill I had to tackle with a 25' camper when I would go camping had me screaming in 2nd gear at 35mph with the transmission and engine temp gauges begging for mercy. The next year with the 5spd, I was doing 55mph in 4th gear up the same hill with the same camper and the truck didn't even break a sweat.

 

[opusd2]

Well, one short financial setback later and the parts are still there and the money isn't as close as what it was. But I think the extra work for the 5 speed is the way to go. I figure I can recoup my money with my pretty little snow plow for sale that everyone wants for free. But about 3 total hours of riding for the parts, and freezing my Eskimo testicles off doing the work, and I should have one nice truck for the road salt to attack.

 

[Greg5OH]

FYI: can get a LUK solid FW conversion kit (brand new hardware, TOB, input, flywheel clutch PP, for $350 from rock auto to your door.
PS i got a manual steering column i could sell ya too, shipping might be a bit pricey though.

 

[The Warden]

FYI: can get a LUK solid FW conversion kit (brand new hardware, TOB, input, flywheel clutch PP, for $350 from rock auto to your door.

I wish that deal had been around when I did my ZF swap...I paid something like $550, plus $100 shipping, for my clutch/solid flywheel setup. That's very hard to argue with!

BTW, it sounds like I"m late to the party, but let me jump on the "Do the ZF swap" bandwagon...you will be VERY thankful you did Granted, I was going from a T-19, but I still contend that the ZF swap was the single best thing I ever did to my truck...