Gear change and High RPM

[guidoverduci]

The T-170 on the receipt and the google search of that casting number is what really threw me off. But the ratio on the t-176 makes sense. 1st is 3.52, 2nd is 2.29, 3rd is 1.46, and 4th 1.00.

I think I might start digging into a trans swap that better suits my setup. Let the games begin!

 

[guidoverduci]

Does the j shift d20 have a 2Lo? If I understand this correctly, it seems I was also chasing something that wasn’t possible.

 

[DirtDonk]

With properly adjusted linkage, there is no 2-low on any Dana 20 after '66 I believe.
With the T-shifts you can sometimes find that spot, but again, it won't lock in willingly if the linkage is adjusted.

Not 100% sure you can find it on a J-shift case, but it's probably possible. The others will know for sure.

Paul

 

[guidoverduci]

Ok.. so dumb question from a 4wd newbie.. I’ve got 4 options for my j shift D20... 4LO, N, 4HI, and 2HI. When the TC is in neutral, the transmission is “disengaged” and nothing will spin. 4lo and 4hi make sense. That just leaves 2Hi. So is that’s where it needs to be for everyday driving?

On a different story, I’m thinking they rebuilt a T-170 case with 176 ratios. Because I don’t have a drain plug only a fill plug. And from my googling, it appears the 170 didn’t have a drain plug.

And another thing I’ve learned in all of this... while playing with RPM gear ratio calculators, and finally figuring out the ratios of my trans, It would appear that my previous setup was in a much better RPM range than what I regear’d to. I went from 3.50 to 4.56 thinking it was going to be a better driving experience, but I’m starting to think that was a mistake the more I learn about all of this!

 

[Broncobowsher]

2HI is correct for normal daily driving. That is standard rear wheel drive, ignores any 4WD parts. That is where you want to be unless it is slick enough that you need the front tires pulling as well. Rain does not qualify as slick enough. Loose dirt or slicker, tires must be allowed to slip to be in 4WD.

4.56 is probably a little much for 35s. But way better than 3.50 gears. I was very happy with 4.88 and 33s, with an overdrive.

Often the lower bolt on the transmission to transfer case adaptor is the drain plug. Cheap manufacturing as one machined hole is both attachment and drain. Remove the bolt and the oil will drain. But the T170/176 is an unknown to me.