Topic: do i have tcase gears?

[toyotajoe35]

How can you tell if you have t case gears with out the case in the truck?

[Duffil]

well, if your truck won't move in low range, you have no tcase gears.

Open the thing up and look at the low speed gears. 
Spin the input while in low range and count revolutions on the output.

[BigMike]

It should be very easy to distinguish all available gear sets.

Shift the t/case into 4wd low range, and mark the position of the input gear and one of the output flanges. Putting both marks at 12 o'clock is good. Now begin turning the input gear taking careful note of its number of revolutions.

If the input gear appears to revolve 2 1/4 times for the output flange to turn once, then you have stock 2.28:1 gears.

If the input gear appears to revolve 4 times for the output flange to turn once, then you have A/A 4.00:1 gears.

If the input gear appears to revolve 4 3/4 times for the output flange to turn once, then you have a 4.70:1 gear set.

If the intput gear appears to revolve 5 times for the output flange to turn once, then you have A/A 4.97:1 gears.

Obvious distinctions include:
For Factory 2.28:1 Gears: A narrow necking on the input gear.
For ANY A/A Gear Set: Very poor quality spline manufacturing and sharp angles near the seal surface.
For a Genuine Marlin Crawler Gear Set: Our Very Own Total-Spline Gear Technology on the Input Gear.
For some early *competitor* 4.70:1 Gear Sets: The cutting or removal of splines without a reheat-treating process from the input gear.

Regards,
BigMike

[toyotajoe35 [OP]]

Thanks so much. I cant wait to see tomorrow.

[BigMike]

It would be nice to also check how many splines the input gear has (21 or 23).

Please see the Marlin Crawler Transfer Case Bible if you would like to know what application the gear drive t/case will fit.