Forum Discussion
jefe_4x4
Mar 21, 2016Explorer
There will be a wide range of opinion on this subject. My bro John has a good yard stick for choosing a transmission: If you're going to tow or carry a lot of weight, the manual 6 speed is the ticket. If you're not, the auto is the way to go. 
The basic foe of the automatic trans is heat. If you can put the largest, most voluminous after market trans oil cooler on; so much the better. Auto transmissions now-o-days are light years ahead of the ones made even a decade ago. The loss in mpg's, visavis a manual has evaporated.
The basic foe of a manual 6 speed is old age.....and the aging driver's knees and back. I've had my NV5600 now for 15 years and I replaced the trans fluid @ 100K miles. That's it. Original clutch. Original everything. However, that 360 pound, cast iron case boat anchor is now obsolete. I hear that it is hard to get parts for it. Something to think about. My bro has the German 6 speed man. ZF-6 in his '99 F-250 diesel and it has been rebuilt twice. The culprit, he found out, was GVWR-ing 20K pounds of truck/camper/trailer/rock racing buggy around using his 'wire' to up the HP in 6th gear. 6th gear is what went south both times. He now tows nothing and has only his OUTFITTER!! on the back. Oh, and he doesn't use as much pedal in 6th any more. If he needs power, he downshifts to 5th. My bro is the only one I know of who has had trouble with the ZF-6.
It's really your preference. Do understand that the ratio of autos to manual in the 99-04 range F series is about 100:1. The ZF-6 sellers think the aluminum case is gold plated, or coated with unobtainium. The 99-04, 7.3L International diesel is legend.
The basic foe of the automatic trans is heat. If you can put the largest, most voluminous after market trans oil cooler on; so much the better. Auto transmissions now-o-days are light years ahead of the ones made even a decade ago. The loss in mpg's, visavis a manual has evaporated.
The basic foe of a manual 6 speed is old age.....and the aging driver's knees and back. I've had my NV5600 now for 15 years and I replaced the trans fluid @ 100K miles. That's it. Original clutch. Original everything. However, that 360 pound, cast iron case boat anchor is now obsolete. I hear that it is hard to get parts for it. Something to think about. My bro has the German 6 speed man. ZF-6 in his '99 F-250 diesel and it has been rebuilt twice. The culprit, he found out, was GVWR-ing 20K pounds of truck/camper/trailer/rock racing buggy around using his 'wire' to up the HP in 6th gear. 6th gear is what went south both times. He now tows nothing and has only his OUTFITTER!! on the back. Oh, and he doesn't use as much pedal in 6th any more. If he needs power, he downshifts to 5th. My bro is the only one I know of who has had trouble with the ZF-6.
It's really your preference. Do understand that the ratio of autos to manual in the 99-04 range F series is about 100:1. The ZF-6 sellers think the aluminum case is gold plated, or coated with unobtainium. The 99-04, 7.3L International diesel is legend.
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