Topic: Dual case's & needing 4wd but not to crawl

[ojm388]

OK so before i get burned too bad im a newb when it comes to dual cases.  My truck is my DD so im not looking to get too crazy.  Im looking at doing the Marlin Ultimate Crawler cases sometime in the future.... I have 2 questions.

1) How do i calculate final gear ratios? i.e 511.1

2) When i need to use 4wd, but not crawl ( getting through mud hunting or trail riding) How will my 4wd be affected?  Im assuming since its no longer stock ratios it will be slower, but just how much?  Will i still have comparable speed in 4wd L & H to stock until i throw the sticks?

[MRHilux87]

Your transfer case, or cases have the option of 4wd hi range even with dual dual cases.  You will be able to use 1/1 gearing in 4wd, just like you currently do.  When it comes to your lower ratio in each t case you have some options. 
Each transfer case has its own set of reduction gears.  Stock I believe is 2.28/1 in low?  and the marlin upgraded one is 4.7/1 in low range.  So If you retain your stock transfer case and just add another one with stock gears in the back case in low you are twice as low.  If you put 4.7/1 gears in the rear case then you go much lower. 
Someone else will explain it better, but thats a start to confuse you. 

[toyodaaddict]

im no expert but ill give my  . I have stock duals, meaning 2.28 in both cases. I spend most of my trail time with the front case in high range and the rear case in low. This gives  the same gearing as a single stock case. When I want crawl speed I put both cases in low. Even with stock gearing in the cases double low is incredibility slow. It is enough gearing that even at an idle I can not stop the truck using the brakes. I have never felt a real need for 4.7 in the rear case but would still like to have it. I am unclear if its hard on the system to run the front 2.28 case in low and the rear 4.7 case in high for long periods of time, when running a 2.28 x 4.7  combo?

 I believe its transmission gear x case gear x case gear(with duals) x diff gear = over all gear ratio of your truck.

[daniresch]

1) transmission 1st gear ratio x ring and pinion ratio x transfer case reduction (x transfer case reduction, if running duals)

Example: 3.75 x 5.29 x 2.28 x 4.7 = 212:1


2) your 4wd will feel the exact same and it only crawls when engaging your transfercase gears

[ojm388 [OP]]

Cool thanks for the reply guys!