38 mm t-case gear tooth count

[Godwin]

The question was posed in some thread recently regarding tooth counts of gears in the split cases with a 38 mm idler shaft. If the question was answered I missed it, so today since I had a case apart I counted gear teeth. Here they are:

Idler, small gear - 24 teeth
idler, large gear - 43 teeth
input gear - 32 teeth
high gear (on main shaft) - 32 teeth
low gear (on main shaft) - 41 teeth
And just for grins the PTO - 31 teeth

 

[FJ40Jim]

Thanks Godwin!

Somebody check the math:

(lg. idler/input) x (low output/sm idler) = low ratio

(43/32) x (41/24) = 2.30

Hey, that's a little better than the 81-85 cases. They're around 2.26, IIRC.

 

[GulfShoresFJ60]

I figured it might be good to have both of the US transfer case ratios in one thread so here we go. 83 FJ60 34mm T-Case

Idler, small gear - 25 teeth
Idler, large gear - 45 teeth
Input gear - 34 teeth
High gear (on main shaft) - 34 teeth
Low gear (on main shaft) - 43 teeth

(high idler/input)X(low output/low idler)

(45/34)x(43/25) = 2.276.

 

[FJ40Jim]

FJ62 tooth count?

The next question:
Does anybody have the tooth count from a 88-90 FJ62 case?
Rumor has it that the gears can be used in a 86-87 manual case, and that the low range is 2.4something.

 

[Cruiserdrew]

Great posts! This should lay all the speculation to rest for all time!

Off topic-Thanks Jim-I got the carb back yesterday and it goes in today.

 

[Godwin]

In a week or so I can add tooth counts for an '85 34 mm split case, which will most likely mirror the counts GulfShores60 has provided.

 

[agent orange]

This link was posted in the thread about the A440f gear ratios.
http://www.birfield.com/~ramullen/FAQ/TEXT/08-01.html

It says the t-case low range for a 3fe with a A440f is 2.296 up to 1990, and 2.488 91-92. It would be interesting to see more about whether the later gears really are that much lower. 60 series production ended in '91 right, with '92 models being '91 production vehicles?

 

[FJ40Jim]

The change shown in the FAQ corresponds to the switch from 60 series to 80 series.

 

[rick_d]

I know for absolute certain, H55 mated tcases
low gears have 38 teeth (I've counted seven or eight in one night alone)
input gears 32 tooth

I am pretty sure that FJ62 cases are the same- someone confirm?

 

[agent orange]

Do 60 and 80 series t-cases interchange as far as the gears go?

 

[FJ40Jim]

I know for absolute certain, H55 mated tcases
low gears have 38 teeth (I've counted seven or eight in one night alone)
input gears 32 tooth
I am pretty sure that FJ62 cases are the same- someone confirm?

Rick, that matches my experience. Every H55 case I've seen has had a 1.99 gearset.

I don't think the 62 case have such a tall low range. I expect they'll be the same as the 86-87 t-cases.

Scratch that, I know they are the same. Just checked the microfiche, there is only one idler gear, with the same 24/43 count, used in all 1986-1990 t-cases.

So it looks like there is no lower OEM low range available for the split case. 2.30 is it.

 

[cruiseroutfit]

That solves the mystery for me...
http://www.cruiseroutfitters.com/tech_split_case.html

But, does anyone know the tooth count on a OE H55F mated split-case with the 1.999?

 

[agent orange]

Would an 80 series case interchange or be close enough to use without to much work for a 62 with an automatic? I was under the impression that 80s used an electronically controlled version of the a440f tranny that comes in the 62. Is there a different bolt pattern for the 80 series case?

-Matt

 

[lowtideride]

Its a full time case though.....(gey)

 

[FJ40Jim]

There's a kit available to fix that weakness.

 

[agent orange]

Thanks for chiming in lowtide, i was thinking about pming you since you have both the 60 and the 80 all apart. Is the 80 series case the same as 60 series case just without a provision for the 2wd/4wd option or is it a different casting? I guess what im asking is whether the difference that makes it full time is something internal that could be changed or whether that would be impossible or too involved.

-Matt

 

[agent orange]

Ahh, my question is already answered, that is interesting to me. Is the kit you mentioned pretty much equivalent to the shifter mechanism of a 62? Im having visions of swapping my parts from my case onto and 80 case and getting a little more gear.

-Matt

 

[lowtideride]

There is a kit I believe to make it a part time case. For the .2 reduction im not sure its worth it.

 

[FJ40Jim]

11/89 FJ62 tooth count

Just to add this confirmation, from a 11/89 FJ62 T-case undergoing reseal:
Tooth counts
input 32T
idler 43 & 24T
hi out 32T
low out 41T

Looks like the same 2.296 ratio as other US 38mm case.

 

[GLTHFJ60]

That solves the mystery for me...
Cruiser Outfitters

But, does anyone know the tooth count on a OE H55F mated split-case with the 1.999?

I'm also interested in this question. Also, anyone know the idler gear size ( 34 or 38 ) and then if the lower US gears can be swapped in?

I got one coming over on a boat, so this would be excellent info for me.