Hi

Tires 33x12,5x16
Label i doorpost shows Trans: K, Axle: C5 .
I just got the car, I am trying to find out what it is.
I will get back when I find out.
Because of this high rpm, it uses a lot of fuel, approx 1,6liter per 10 kilometer, that must be something like 14mpg?
Snubber

 

Wow guys...this is turning into quite the thread..thought I would mention that (as far as I know) the E350 vans (cube I'm looking for) only came with auto trannys. I also assume that there was only one auto transmission available so the best highway gearing for me would be determined only by rear axle ratio and tire size.

...or am I out to lunch on there only being one auto tranny/ratio???

 

dave i think you are right, its 513 or worse. ha i looked at my tires today and they are 245/75 X 16 and measure 30 or slightly more inches in diameter. we had talked about this truck earlier when it had the bad engine. well i had a rebuilt 7.3 installed and thats when i found out it was so slow. i also found out the lay shaft or main shaft in the transmission has bad bearings. as i am changing axel ratio's i will freshen up the transmission also. i looked at the rearend in the truck today and it is very heavy duty and i also found out it has disc brakes on the rear. i also think the rearend has been switched out recently, because it has a yellow marking on it that says 71k. ( like it came out of a wrecking yard.) it may be a newer rear in this truck.

 

snubber, i have been told 2200 rpm is good for cruising and my mechanic said not to cruise my truck at more than that. there is no way 50 mph is going to do the job for me. my driving will be mostly hiway driving.

 

my truck is a 98 model 7.3 diesel with a zf 5 speed transmission and it has a 4.10 rear end, the speedometer reads 70 mph and the tach reads 2700-2750 rpms. my grandpa's truck is a 93 7.3 diesel with a zf5 with 3.55 rear end and the speedometer says 70 mph and the tach says 2200 rpms. like i said, your truck has 3.55 rear ends if it runs 2200 rpms at 70. there is no difference between the 5th gear ratios from 89 zf5 to 93 zf5. so unless you want me to drive to washington and hook bumpers with you and drag you in circles and down the road backwards to show you that my truck has 4.10's and yours has 3.55's, you should just believe me. i have driven trucks with 3.55, 3.73, 4.10, and 5.13. all with zf5's and 7.3 diesel. i know my ****. the one with 5.13 would run only about 65-70 wide-*** open. it was sad. so unless you are saying that my grandpa's truck has 4.10's and my truck has 5.13's and the truck i thought i drove with 5.13's actually had something lower geared than that. i don;t know what your talking about. but some people just don't listen. and are ignorant and talk about stuff when they don't know what they are talking about. how many rpm's would a truck with 3.55's run at 70 going by daves calculations???? it would be somewhere about 1500. i don't think anybody in here has a truck that runs 1500 at 70. ya'll take a vote and tell me who makes more sense please.

 

plus there aint no way in the world that diesel weasel could get 20 mpg with 4.10's just aint gunna happen

 

89 ford 160k.on 22.5 liters of fuel check 2200 on tack with gps 108.8 k this is with 315x75x16 =34 inch know my gears rebuilt rear axle ihad owned 250 fords for about 28 years .played with evert thing possible owned my auto shop for 20 years have been in stock car and drag racing so i know alittle about gearing and rpm

 

Well since I am using engine speed, transmission ratio, differential ratio, and tire diameter to calculate the speed it will run, I KNOW MY NUMBERS ARE RIGHT.

I do not care what the speedometer says. I have seen to many that were wrong.

So here you go
2050 RPM
ZF 5 in 5th
3.55 rear
31" tires ( 235/85-16 )
70.072362 MPH

Take the same truck with 4.10's and it will turn 2368 RPM at 70.084034 MPH

And if you look at weasels posts I bet he is in Canada which has Imperial Gallons and uses Kilometers instead of miles.

 

well i dont know nothin about no imperial gallons and stuff metric scale b.s. all i know is that he can't get no 20 us miles per no u.s. gallon unless he drove 100 miles to work and back every day at about 45 mph. my truck with zf 5 has a axle code of c5, thats 4.10 posi. 2700 at 70. my grandpas zf 5 has a code of 39, thats 3.55 regular. 2200 at 70. he bought both trucks new and has never had the rear end gears out of either one of them. the tranny's are original and never been opened up on either of them. so you go tell ford that they marked all the axle codes wrong on all their trucks i guess if you want too. unless both my granda's and my clutch slips 500 rpms at 70 mph for some unknown reason... i have driven many trucks with 3.55's and they all ran 2200 at 70 accept for the one that had a e40d, and it ran 1800 at 70 i have mines the only truck that runs 2700 at 70 that i have driven and it has 4.10 the one with 5.13's would barely do 75 wide open 3300 rpm. harley john. 2200 is a good cruzing speed, but don't be scerd of it, that old ford aint gunna blow up, mines been driven at 2700 for the last 300,000 miles and aint hurt it yet. hey dave, what is the axle code on your truck say?, i have never heard you mention that one.

 

Hi

I was wondering, Trans code K, will that mean I have a C6 trans in mine?
snubber

 

89 ford 73 in responce to your hundred miles at 45 mph i do round trips of400 to 450 miles once or twice a week at 100k or 63 mph

 

89ford73,

Well I do not know off the top of my head, I do not care, I had the differential apart and counted the teeth and know I have a 3.55 rear. What the door or tag on the axle say does not mean squat.
The tag on my front axle says 3.54
The tag on my rear axle says 4.56
But it drives just fine in 4x4 so one of them is wrong.
Ask any mechanic how many wrong tags they have seen on vehicles.

Numbers do not lie.
Speedometers are wrong very often.
Tachometers are also not absolute gospel.

You must be young to not be aware that anything made by man is subject to mistakes.

 

Have a '93 idi factory turbo with the zf 5 and the 4.10 differential and it does about 64 MPH at 2000 RPM...

 

Okay Guys , let's put the brakes to these personal comments directed at others.

Keep personal thoughts to yourself & stay within the guideline's .

 

If you have the axle code and have an owners manual the ratio will be in there. I have 5spd manual and my axle code says I have a 4:10. I do 2200rpm @50Mph, A 4:10 is rough around town though