I am attempting to ring a little more MPG from our F350/460 work truck.
The local self service JY is beginning to get in some of the manual F350 gassers
The trannies go for a <$200. price.
Were the early ZF 5 speeds behind gassers any good or am I just opening another can of worms.
The current c6 / 354 works fine I just want to explore all options.
Wonder what mpg improvement I would get with an ZF 5 speed OD manual vers the C6 slush box.
Would it ever pay for its self??
But there is nothing like a big engine and a manual.
Does anyone have any first hand experience with the ZF 5 speed behind an FI 460 in an F350?

 

They are nice transmissions in my opinion.
They shift fine. The one behind my 460 has endured hell and then some.

 

The ZF5 came out in 1987 as an option, it's called the ZF5 S42, the later model (S47) witch came out in 1995 is the stronger one. But the S42 will handle the stock 460 no problem.


You should gain at least 2-3mpg more with an OD gear.

 

My 88 F250 With 117000 miles on it runs and shifts awsome. Grandpa bought the truck new in 88 and used it to pull his horse trailer, camp trailer, and flatbed for years. He passed 4 months ago and I got the truck. I don't see any reason why the trans won't last another 20 years

 

My ZF5 has 377k miles behind my 7.3 Diesel. All original.

 

The naming convention is as follows:

ZF 5 (5 sp) S (syncronized) 42 (420 ft/lbs)

ZF 5 (5 sp) S (syncronized) 47 (470 ft/lbs)

I have over 500K on mine behind a 5.8L gasser, though I rebuilt mine somewhere between the 250-300K range because one of the syncros decided to de-syncro-nate (disintegrate).

Rare occurrence actually, they're very nicely made transmissions.

Regarding MPG, that depends on how you shift. Bang redline a lot and you'll use far more gas. When I'm driving locally, I tend to shift "crazy low" since there's no point in accelerating hard around here with all the windy residental roads. So by 25 mph, I'm generally in overdrive.

 

Where are you located that you can find ZF's for 200?? Would like to find around Indiana for that price.

 

I saw a ZF for $350 once..only 75,000 miles. I should have got it

 

I have an np435 I was going to put in the F350 but if I can find a newer Z5 tranny at the pick-n-pull price I would be better off.
The key to the good price is to find the ZF at pick-n-pull.

 

Turns out its still there
3/4 ton Ford 5 speed transmission

 

I think most of us were thinking 460 transmissions.
That one you posted is for a smallblock and the 300-6.
Thanks for the link though.

 

I was talking about for my 302 and the fact its $300

 

That's cheap no matter what.
If you're wanting a 5spd I'd go for it.

 

I have about 215,000 in mine and it has served me very well. On a ZF you MUST use ATF as the lube the tolerances and clearances are that tight .... any thing else will NOT get into all the areas needed. I use 1/2 cup of Lucas oil treatment each change and NO more just because I am bullheaded. I have a friend who went to school on the ZF and he loves them cuz of their durability ... but they are NOT cheap to fix. I only run the Lucas in the summer because of the Vegas area heat all in all GREAT trans. Dave

 

Yeah a used one is usually $500-$800
Rebuilts are like $800-$1200, usually on the higher end.