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diddycj5
01-08-2004, 03:54 PM
I am thinking about twin sticking a dana20 - why? because it would be too easy to do it to a D300. However, I have seen conflicting info in magazines and online about removing the interlock pins on the shift rails. Most info says to remove them and be careful when shifting to make sure front/rear are the same (rear low & front high would be bad). However, some info says that the t-case will not stay in rear low due to a taper on the shift rails.
http://members.dialstar.com/ezduzit/twin20.htm

I know that some early scout dana20's actually came twin sticked from the factory. Something doesnt seem to add up. Is there any difference between scout shift rods and jeep? I haven't pulled my dana20 yet and start rebuilding it so I have never had one apart.

Since there is so much flat out wrong info in magazines and online I thought I would post this to the experts on bulltear.

If the stock dana20 shift rail really shouldn't have the interlock pins removed due to the taper of the detent - this could be a new bulltear product: Dana20 shift rails that work for twin sticking.

jeepsr4ever
01-08-2004, 05:52 PM
Here is my experience


1. I have never seen a tapered shift rod, seen cases on jeeps from 67-79
2. The pins that hold the shift rods together and inline can easily be taken in and out
3. Their is no reason why you cant take the rods off and move the stubs in and out, i have been shifting like that for years.
4. Did that help?

Toy Maker
01-09-2004, 06:24 AM
I have been running twin sticks on a dana 20 for 12+ years without problems. The detent balls (that are beneath the rods) hold the rods in gear, the interlock pins (that are between the rods) sequence the shifts. Remove the pins, leave the balls with springs. DO be carefull not to mis-match shifts. Severe binding and possable breakage can result.

diddycj5
01-12-2004, 02:33 PM
I have been running twin sticks on a dana 20 for 12+ years without problems. The detent balls (that are beneath the rods) hold the rods in gear, the interlock pins (that are between the rods) sequence the shifts. Remove the pins, leave the balls with springs. DO be carefull not to mis-match shifts. Severe binding and possable breakage can result.

Does this give you all possible combinations of gearing (rear low or FWD high/low.) I was told that twin-stick dana20 with stock interlocks/shiftrails would only add rear low to the High/4High/4Low stock combination.

Toy Maker
01-22-2004, 06:13 AM
With the interlock pins removed, I can use front high, neutral, and low, and/or rear high, neutral, or low. Front only, or rear only or any combination of both. They are shifted seperatly and independantly.

diddycj5
01-22-2004, 10:19 AM
Have you had any problems with the D20 popping out of rear once you removed the interlock pins?

Also, I have heard so many conflicting information about what gear combinations are possible if you do not remove the interlock pins. Some people say, all you add is rear low. Some people say that you gain nothing from stock: rear-high, neutral, 4-high, 4-low. How are that many people confused or wrong. Or is there differences in the interlock/twin sticking with different D20's over the years?

Toy Maker
01-23-2004, 06:28 AM
I have never had any problem with jumping out of any gear with my twin stick setup. As I said in the previous post, it is the detent balls that hold the shift rails in gear, not the interlock pins. If the interlock pins are not removed and the rods and pins are in good condition, the case will not shift into 2wd low, with or without twin stick. Twin sticking does nothing. If the rails and/or pins are sufficiently worn, then twin stick can give 2wd low along with normal shifts. With worn rods/pins it is possible to get 2wd low with experience with most shifters (not the Comando, GW or Jxx) without twin sticks. I used this for many years before doing the twin stick, and occasionaly it would try to slip out of 2wd low, as it was not fully engaging the shifter, only bypassing the worn interlock.
To have full control and reliability, you must remove the interlock pins.

diddycj5
01-23-2004, 09:52 AM
Thanks for the clarification. What you said about the interlock pins being worn and possibly getting 2wd low makes sense why I was getting multiple conflicting stories. Can you remove the interlock pins without fully dissassmebling the t-case or can you get them out through the casting that houses the shift rod seals? - I have never done anything with my D20 other than take it off my old T15 and install it on the T18 when I was doing the tranny swap. I am still trying to learn as much as I can about the t-case before I criple my jeep and start pulling everything apart.

Toy Maker
01-24-2004, 08:16 AM
The interlock pins are about the last thing you get to in dis-assembiling the transfercase. Plan on doing bearings and seals while you are at it.

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