i have a 1978 F 7000 5 yd dump with cat 3208 and 5 speed clark transmission. the truck has 2 speed rear axle, but geared way too low for my use. is there a simple way to figure out what ratio rear end i have? thanks.

 

Welcome to FTE

Post the AXLE code found on the Warranty Plate, located on the left door face below the latch.

 

Bill's advise is good, as long as it was never changed for some reason.

Simple way would be to jack both wheels off the ground, put the tranny in neutral (chocking the front wheels VERY well). Using a piece of chalk, mark the driveshaft at the lowest spot near where it connects to the rear. Mark one (or both) of the wheels with chalk too. Turn the driveshaft by hand, counting how many times you have to turn it to make the wheels turn one complete rotation.

If it's a two-speed, do it with the rear in each gear. Report back

 

you guys are good. thanks. the truck vin is K70BVAJ5152 and the axle code appears to be EHH.

 

K70 = F700 (diesel).

B = Caterpillar 636 cid V8 diesel / Model V190-3208.

V = Kentucky Truck Assembly Plant.

AJ5152 = 1978.

AXLE code EHH:

EH = Eaton model 17221 2 speed rear axle / 5.56/7.60-1 / 18,500 lb. rear axle capacity.

E = Ford front axle / 7,500 lb. front axle capacity.

 

bill the data plate calls out transmission 2. as this transmission has no tags on it, can you identify it as well? thanks bill. mike

 

2 = Clark Model 282V 5 Speed Direct.

FYI: The 1973/79 Ford HEAVY Truck Parts Catalog is available on a CD from hipoparts.com. I'm using this catalog on Ford microfiche slides.

 

thanks bill. i just bought the cd for my truck. thanks for the help. mike

 

Even with 42" tires, you are pushing 3000 rpm at 65 it looks like.

Probably the easiest change would be an OD Clark or other OD trans in place of your direct trans.

Maybe some help here:

Clark Transmission Rebuilding | Exchange Clark Transmissions

 

Bill
i'm playing with the new CD you suggested. trying to understand how it works. earlier you called out with axle code EHH a 18,500# rear axle, with 7,500 front axle. when i look i see H code for front axle calls out 12,000 # ford front axle. am i doing something wrong? thanks. mike

 

1978 was the last year Ford had sold the B-7000 and the F-7000 with the "V636" branded 3208. The two models would not return until 1983 (production start: August 1982), when Ford also revived the F-8000 and the FT-8000 (the latter was originally T-8000).

All of these, as before, had the 175-hp Cat 3208 as standard equipment (through 1986, when Ford started cataloging the 6.6L and 7.8L turbo six-bangers). The turbocharged 3208T (225 hp @ 2600 rpm) would join the fray in February 1983.

The standard V636 engine for your F-7000 is rated 175 hp, but it could also be specified with the 210 hp version. California trucks used the 200 hp V636 engine.

For those wanting to know the gear ratios to the 282V, go here:
Transmission ratios
(and then scroll down to 282V)

Engine: Ford-Caterpillar V636 (3208), 175 hp @ 2800 rpm
Rear axle: Eaton 17221
Ratios: 5.58/6.77
Engine speed at 45 MPH with tire size 10.00x20: 2111/2561
Max. speed MPH at engine speed: 59.7/49.2

For mjsnodgrass: How big are your tires, if not 10.00x20 or 11R22.5?

Thank you,



Ben

 

Please help decipher rear end tag wev-AA1-7ED. 0075. 9 718A