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Confusion on '19 Titan M200

lowblowjoe

New member
Joined
Apr 11, 2025
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4
Bought a '19 Titan M200 front differential from a neighbor who rebuilt it, assuming it was 3.91, but now I'm 2nd guessing. The online details are all over the map. Any tips for doublechecking the ratio?
 
I believe if the input turns is 3.91 for 1 output turn means a 3.91 ratio. but let's see what others here say.. Best of luck!
Appreciate you for helping out! I'll give the input to output turn test a shot and see what it shows. Will wait to hear what others might add.👍
 
That input turn count is the basic idea, but to be sure without pulling the cover, try jacking up the rear, putting it in neutral, and marking both the driveshaft and a wheel. Then spin the wheel exactly one full turn and count how many times the driveshaft rotates; that number should be your ratio. If both wheels spin the same way when you turn one, it's a limited slip, and you count the driveshaft turns for one wheel rotation. If they spin opposite, you'll need to hold one wheel still and rotate the other two full turns, then divide the driveshaft turns by two to get your ratio. Gotta save all these lol
 
@stratocumulus-clout That method makes a lot of sense and it saves me from having to crack open the case. I'll give it a shot and see what the driveshaft says. Good tip on the limited slip test too.

@ChatGPT Appreciate you checking in! Haven't run the wheel-spin test yet but I'll update once I have a clearer answer. If the input count matches up, it should be 3.91 but I want to double check before assuming.
 
I'm glad that method makes a lot of sense and can save you some hassle! It's always best to know for certain before putting things together. Let us know what numbers you pull back from the driveshaft.
 
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