Topic: Top Shift V Forward Shift information request

[pray4surf]

I'm looking for some input on the forward shift tcases that came on the 4-cyl automatic tranny tacoma's. Getting ready to re-start a PreRunner to 4wd conversion. It was during my first attempt that I became faced with the 'problem' of the 6-cyl tcase top shifter that positioned the tcase shifter to far aft. While I have a 'work-around'* figured out, I thought I'd investigate the top shift vs forward shift arrangements.

Lengthy internet researching has failed to turn up any pics / schematics that clearly explained the differences.

During my first attempt, I installed an 04 A340F trans and tcase. The following picture shows the shifter positioning problem...



But due to a 'throttle-by-wire' arrangement on the 04 transmission, I had to scuttle that attempt as my truck (1998) couldn't/wouldn't support the electronic issues. Since then I have picked up a A340F tranny out of a 99 4Runner that employs a mechanical TV cable. This 99 A340F looks like it may support a forward shift arrangement as it has a plate in the tailhousing.

Pic of 04 A340F



Pic of 99 A340F







What light can you shed on the Forward Shift arrangement? Does that access plate in the tailhousing 'support' this forward shift arrangement?

*Work-around* - simply, I'd cut the shifter lever into a top / bottom and welding a short piece of 1/4"T "pushing" the top half of the Shifter lever forward.

[kiyul4130]

tell me if im incorrect but it looks like what your trying to do is just see if a forward shift will work in your 99 A340F so the shifter can clear the body, correct? it looks like all you'll need to do is just find a forward shift t-case and throw it in there (allowing you to not have to cut the floor) that or mod the top shift rails turning them into forward shift rails in the last picture so you can throw on a base plate and have the shifter there. (then youd have to find another plate for the actual case) my question is about the first picture, why dont you just cut the floor back a little bit and run it like that then it would allow you to run a tranny thats 5 years newer.  hopefully this doesnt sound confusing, i think ive almost confused myself.

[boggerunner]

i say cut the floor, alot and flat belly it like this

[kiyul4130]

im just assuming its a newer truck and whoever owns it doesnt want to hack it up.

[pray4surf [OP]]

tell me if im incorrect but it looks like what your trying to do is just see if a forward shift will work in your 99 A340F so the shifter can clear the body, correct? it looks like all you'll need to do is just find a forward shift t-case and throw it in there (allowing you to not have to cut the floor) that or mod the top shift rails turning them into forward shift rails in the last picture so you can throw on a base plate and have the shifter there. (then youd have to find another plate for the actual case) my question is about the first picture, why dont you just cut the floor back a little bit and run it like that then it would allow you to run a tranny thats 5 years newer.  hopefully this doesnt sound confusing, i think ive almost confused myself.

You are right, but it is not a newer truck (it's a 1998). The 4-cyl forward shift tcases have a different input shaft (spline count) than the 6-cyl tcase (26 vs 23) Basically, the forward shift tcases can only bolt up to a 4cyl 4x4 A340F trans. So far, this workaround is looking better all the time

I know that Marlin specializes in manual trannies, but hoped that someone here had some pics or...

I can't use the 04 Trans due to the electronic throttle-by-wire issue.

By the way, I am on the hunt for a portion of the tcase wiring harness - for the three position sensors back to the ECU

PSS - That 04 trans and tcase is for sale 54,000 miles

PSSS - I think I understand what you are saying re the shift rails. Would like to see an exploded view diagram (can't find anything in the FSM hosted at the NCTTORA site) of the assy - At least that would give me some part numbers to work with. Toyota parts has suggested that I obtain a VIN from a 4cyl 4x4 automatic.

[kiyul4130]

You are right, but it is not a newer truck (it's a 1998). The 4-cyl forward shift tcases have a different input shaft (spline count) than the 6-cyl tcase (26 vs 23)

1998, not new?! ya maybe not, but comparing to the average person that builds a toyota its an EARLY 90's or older. ya i knew the spline count was different between the 4 an 6. just didnt know the count. i know the older ones are 27 and 30.