Topic: How to Calculate total crawl ratio???

[8Snaces]

Hey. I was wondering if anyone could tell me how to calculate the total crawl ratio. What x what x?? divided by ?? .... Thanx!!!

[MiniSimp]

(First gear) x (first transfer case low) x (second transfer case low) x (axle ratio) = crawl ratio

Just adjust the formula for how many crawl boxes you have. In Mike's case, 3

[jimbo74]

http://www.marlincrawler.com/htm/transfercase/getratio.htm

Multiply your first gear, times your low range transfer case gear, times your differential gear

[jimbo74]

i have a 36.74 crawl ratio

[8Snaces [OP]]

Thanx!!!

[8Snaces [OP]]

Ok... so. 81 toyota pickup... says it has an L50 in it. OK.. no prob.
3.93x2.28x2.28x5.29=108:1.

[Chevyboy_0]

What is a crawl ratio?

[MiniSimp]

What is a crawl ratio?

How slow you go.

The higher the number, the slower you are.

[Chevyboy_0]

What is the average crawl ratio of an 86?

[MiniSimp]

What is the average crawl ratio of an 86?

36.74 rounded up.

[8Snaces [OP]]

If i change out my rear case from dual stock cases to stock front & 4.7 rear, i pretty double my ratio. Thats SIK!!!!!

[jimbo74]

What is the average crawl ratio of an 86?

36.74 rounded up.

yup, unless you have a turbo truck



36.73764 for a stock 22r or re

[BigMike]

"Crawl Ratio" is the ratio of the Engine speed (RPM) versus the Tire speed (RPM).

So a 2:1 Crawl Ratio means that when the engine is turning at 800 RPM, then the tires are turning at 400 RPM, when on a flat frictionless surface.

The exact method of calculating a Crawl Ratio is to know each tooth count of every individual gear between the Engine Crank Shaft (Engine RPM value) and the Tire.

For instance, a W56's 1st gear is said to be 3.95:1, which is derived from it's input-to-counter shaft ratio of 1.46875 (47 teeth on the counter shaft divided by 32 teeth on the input shaft) multiplied by the counter shaft-to-output ratio of 2.692307 (35 teeth on the output shaft divided by 13 on the counter shaft), which equals 3.95432590625:1, or 3.95:1.

Then once all of the torque reduction (or multiplication) gear trains are multiplied together, you get the final reduction (or multiplication) from the Engine Crank Shaft to the Tire.


Before the Marlin Crawler came out, the "best" Crawl Ratio for a Hilux truck was around 48:1 - 51:1. Since the Marlin Crawler came out (1994), common Hilux Crawl Ratios are now 84:1, 98:1, 108:1, 223:1, ..etc.

[8Snaces [OP]]

Thanx everyone!!

[Wermz84]

So my first attempt at a build up will have a 98:1.    how very medium.  haha

3.93X4.70X5.29

[mima]

i'm happy with my 98:1... but then again i dont like to go too slow...

[8Snaces [OP]]

Wermz... only gonna run a single case? Thats kewl. I was playing around in single low over the weekend. I hadnt done it in a while... it was pretty kewl!! I think that some of my buddies are goin down this weekend to HH. I mite be goin.. i dunno yet. Still workin bugs outta the truck. I will let u know tho. Gotta play with dual low and a particular rock pit that i havent run b4. HEHEHE!!