auto to manual conversion questions

toocoolpowerstrk · Jan 4, 2012

So i am getting ready to start a auto to manual conversion in my 02 f250 cc psd and i was wandering if the transfercase from my automatic will bolt up to the my zf6.

HaysKSFirefighter · Jan 4, 2012

I'm fairly certain the tc will bolt up but you'll need different length drive shafts...don't hold me to that though. You'll love the zf6 though...I got rid of my 02 and upgraded to an 07 with one and I'll never go back.

Denver · Jan 5, 2012

It will not bolt up. Splines are different.

lowbedriver · Jan 5, 2012

:whs: new shaft for the transfer case is about 200 iirc

Charles · Jan 5, 2012

Shaft splines are different, but the driveshaft lengths are identical. I know this after getting that God-forsaken excuse of a transmission out of my truck and installing a 4R100.

I recently lost the one in the 550 as well. They can't take the towing. Good luck destroying a good truck by putting an inferior trans in it.

The truck will be slower, have reduced driveability for any given power and be capable of less continuous power output when towing due to trans overheating.

Facts.

I'm sure that won't even slow you down. It usually takes a year or two before the guys that do this learn the above facts the hard way.

lowbedriver · Jan 5, 2012

Charles do you know what temps you had when towing and how much weight?

Arisley · Jan 5, 2012

Charles said:
Shaft splines are different, but the driveshaft lengths are identical. I know this after getting that God-forsaken excuse of a transmission out of my truck and installing a 4R100.

I recently lost the one in the 550 as well. They can't take the towing. Good luck destroying a good truck by putting an inferior trans in it.

The truck will be slower, have reduced driveability for any given power and be capable of less continuous power output when towing due to trans overheating.

Facts.

I'm sure that won't even slow you down. It usually takes a year or two before the guys that do this learn the above facts the hard way.

Back in the day, I used to love standards. After being out towed, out raced and out lasted by lowly Turbo 350's and 400's. I was leaning towards an auto. When I saw a really lowly two speed slip and slide (Circa 1961) pull hard up over 120 MPH, I was sold. I do not care what tranny you have, you cannot out shift an auto. Unless you are a semi, pulling huge amounts of weight, an auto will do everythig a standard will do, and do it better.

Charles · Jan 6, 2012

lowbedriver said:
Charles do you know what temps you had when towing and how much weight?

The load that I roasted the first ZF6 with in my Red truck was usually my F-350 trail truck on a bumper pull equipment trailer. It was only ~20,000 gross, but I rocked 75 to 80mph back in the day, not realizing the driveline was dying. It turned the fluid dark black in the trans and the rear differential and pushed the needles in the u-joint caps into the trunions....twice....

I gave up, replaced the trans with a 4R100 and rebuild the rear diff. I have since replaced a driveshaft u-joint from heat again, but the trans has never gotten hot like the ZF6 did.

In the 550 the hardest pull is the usual load of 18 4 x 5 round bales on a 24' gooseneck at ~75mph. About a month ago I swapped out the ZF6 because it wouldn't stay in gear anymore and the fluid had scorched bad and hadn't long since been changed. About a week ago I rebuild the third member in the Dana 135 because it melted the ring side carrier bearing until the ring gear was no longer in contact with the pinion.

The moral of the story is that a well tuned 7.3 will see the demise of the driveline in one of these trucks, and that the 4R100 seems to be able to hang in there longer than anything else when the continuous load of full power towing is allowed to run its course for a few hours at a time. The ZF6 and the axles give it up. The 4R stays the course. I have towed the identical trailer of hay with my Red truck at a higher speed and while I completely emptied the water injection tank 3 times, the trans fluid still looks brand new.

At this point I'm thinking of getting a little single axle tractor to replace the 550. It is apparently not enough truck to support its own engine.

lowbedriver · Jan 6, 2012

Do you think if you put the same size cooler as the 4r has on the zf6 that would have helped? As far as the rear I cooked the carrier bearings on mine at 60k towing a 5th at 75 thru the desert.
What about adding an aux cooler to the diff? How much weight are you carrying on the drive axle?If its close to max you probably would be better off with single axle tractor
We installed elec. fan cooled trans coolers on our 18spd when trans temps where getting up to 300 hauling 200,000lbs no problems since trans never gets over 210 anymore

toocoolpowerstrk · Jan 6, 2012

lowbedriver said:
:whs: new shaft for the transfer case is about 200 iirc

what is iirc? the only reason i am even considering putting a zf6 in my truck is i have pulled and driven a 05 350 with the zf6 trans and i loved it and now i will say that an auto is a really good trans but i just love shifting personally. the auto i have now is starting to act up on me as it is anyway, im sure its nothing that a filter kit wont fix but im thinkin now time better than now so what the heck. i love standard transmissions and probably always will.