I am looking to find out what the gear ratios arew for the zf 5 spd and wondering how strong they are. I have had to change many due to cracked cases or bellhousings. (should i stick with my NP435?)

 

5.72 2.94 1.81 0.76 | 5.24 or
4.14 2.37 1.42 0.77 | 3.79 in '95.

 

The wide ratio (5.72/0.76) is primarily for gas engines, the close ratio (4.14/0.77) is for diesel engines. I have a sheet that says the wide ratio was an option with the diesel. I believe the ZF is rated at 350 ft-lbs.

 

the S5-42 is rated for 420ft/lbs

 

For comparison, the NP435 ratios are: 6.69, 3.34, 1.79, 1.00, rev- 8.26. There was also a close-ratio NP435, but I don't think it was used in Ford trucks.

If you don't like the one-piece aluminum case and hydraulic clutch of the ZF, but still want a tranny with a granny and an overdrive, you may want to look into the NV4500, which is an iron-cased granny tranny with a seperate bellhousing and top-shifter like the NP435, but with an overdrive tailsection .

NV4500 ratios for the Dodge version are: 5.61, 3.04, 1.67, 1.00, 0.74, rev- 5.61 or 5.04. This was used in Dodge and GM trucks in the '90's. The early GM version has wider ratios (6.34 first), but isn't as easily adapted to other engines, from what I hear.

 

Thanks guys I think that I'll just keep my np435 it's always been good to me and i wanta keep that low granny and reverse.

 

This is a good chart. It has all the popular manual tranmission gear ratios.
http://www.fordsix.com/trucktranny.htm

 

maybe it's just me, but where's the 5th gear?? you only have 4 gear ratios plus reverse....

also, what's the difference between a T-18 and a NP435??? I've got a T-18 in my 1/2 ton 4x4, and love it, but i'm looking at a F-250 4x4 with the NP435??? is the NP got a synchro'd 1st? what're the gear ratios for the two of them??? curious...thanks

MontanaFord

 

The fourth gear is 1.00 for both close ratio and wide ratio versions. 5th is the OD 0.77/0.76.

 

which of the T-18's would my 84 F-150 have?? apparently, there were 3 of them available...A, B, and C....anybody got an idea??

MontanaFord

 

Montana Ford, both the NP435 and the T18 are only synchro'd on 2nd through 4th gears. No synchro on 1st or reverse. Both are iron case heavy duty trans with PTO provision. The T18 is one inch longer than the NP435 and the ones used in Fords are interchangeable as far as mounting bolt patterns and input/output shafts. The trans you're thinking of with full-synchro gears is the T19, which is very similar to the T18.

The T18A ratios are: 6.32, 3.09, 1.69, 1.00, rev- 7.44.
The close ratio T18 and T19 ratios are: 4.02, 2.41, 1.41, 1.00, rev- 4.73.
The T18B ratios are: 4.32, 2.26, 1.51, 1.00, rev- ?
Another T19 ratio set is: 5.11, 3.03, 1.79, 1.00, rev- ?