Crawl gear fr my 5spd Bj42!

[Klaufi]

Evening,
I am looking for a crawl gear for my '84 bj42, 3B, 5speed.
What is my T/C called?
And who makes crawl gears for them?

Want lower gears, but don't want to loose my current low range for when the snow is good.
Already running 4.88's and 38".

 

[dslcruzr]

I believe Marlin is making toyboxes for 5speeds, and is probably the nicest option. Your transmission is a h55 (f?) and i you should have the later "split case" transfer case. I'm looking into going lower as well, and have a very similar set-up as you. I'm just getting around to putting in 4.88's. Let's see some pics of your rig!

 

[Klaufi]

thank you, I thought that the toyboxes wouldn't fit. Have you decided wich gearing to ewuip the toybox with?
I hear you can pick different gearings their site is down atm so i can't read about them atm .


*EDIT* Wroe so muchabout my car i decided to start a build thread instead!
https://forum.ih8mud.com/40-55-series-tech/221088-build-thread-84-bj42-iceland-bunch-o-pix.html

 

[Diesel42]

Awesome pics and awesome rig. Where were those photos taken at? It seems there is a place called Marks gears that sells a full compliment of gear sets for your(our) transfer cases. Very expensive though, seems like 1800 or 2000.00USD if i remember right. Give or take a couple hundred still way spendy. I would also like to do this mod. Welcome to the forum.

 

[simonliew]

Hi,
l have installed 2 Toyboxes on Bj42s,one with 4 speed H42 and one with H55F 5 speed.l moved the engine forward 4" and therear axle back 3",the toybox has 4.7 low.
Marks' gear in australia have 1.08 hi/3.08 low gears that will fit in your split transfercase.
Simon
Winnipeg

 

[Klaufi]

Diesel42:
Thanks, Pics are taken in Iceland, More pics in my build thread

And Simon:
Why did you move the engine?
Why notchange the lenghtf the driveshafts?



Lke i said, i want an additional gear, i don't wantto change the original transfer case, the origial low gear is sometimes good in snow, and for very heavy snow i need lower gears, but don't want onlylower gears ecause then i will be travelling a hell of a lot slower when the snow isn't that heavy

 

[freebie]

Hi
Very nice rig!
I just put an H55f in my Bj42 and the rear driveshaft ends about 19" long flange to flange. If you take off the u-joints and the slider the tube is 3-4 inches long. Not much room left for any thing else unless you want to go full on front wheel drive?

Cheers and enjoy mud!

 

[simonliew]

Hi Klaufi,
my project is a rockkrawler,the toybox is about 7" if l remember right,with springover axle suspension,l ended with a very short driveshaft(about13") if l don't move the engine and rear axle.
Where ca nl buy those rear femderflares,l have 80 series axles and 40"x17" MTRs.
Simon

 

[crushers]

hint, if you want a lower low range but not 'rock crawling" low then get a t/case from an auto HJ60 and swap in the gears. the final crawl is the same as if you changed out the rear gears to 4.88... i have done this swap on many of my bush rigs and love the result.

the the t/case aftermarket gears seem to howl a LOT.

i have seen the crawler box installed into a couple trucks and it really gives them some serious crawl ratios but a 40/42 will need some major mods to fit (i.e. what Simon did) definately not a bolt up and run...

 

[Tapage]

hint, if you want a lower low range but not 'rock crawling" low then get a t/case from an auto HJ60 and swap in the gears.

are 2.48:1 vs 2.28:1 in the gassers and 1.96:1 in diesels ..

 

[Klaufi]

Simonliew:
Thoose fender lares are built here in Iceland, they are plastic, If my memory doesn't fail me a comapny that builds plastic boats makes them. Originally made for the Cj-7 Jeep.

All others talking about drive shaft length:

I don't think i have to worry about the drive shaft lengths since i'm talking about extending the car, the extension will be made just behind the T/c, so i have plenty of room for shaft's. The front shaft will ecome a little longer and the rear shaft will also need to be extended.

P.s. Simon, look at this 80 series's flares on 44" Lots of thoose here in Iceland

 

[brisveganbj42]

I'm interested in this mod..

hint, if you want a lower low range but not 'rock crawling" low then get a t/case from an auto HJ60 and swap in the gears. the final crawl is the same as if you changed out the rear gears to 4.88... i have done this swap on many of my bush rigs and love the result.

from the info I have found the low range ratio in my bj42 is 1.959:1.

are 2.48:1 vs 2.28:1 in the gassers and 1.96:1 in diesels ..

What is the low range ratio in the HJ60 transfer (is it an A440 g/b?).

 

[crushers]

the BJ42 5 spd comes with the 1.9 low
the BJ42 4 spd comes with the 2.3 low
the HJ60 auto comes with the 2.48 low

4.9 (H55F 1st) X 1.9 (low range) X 4.11 (diff gear) = 38.26 crawl BJ42 5 spd NA spec
4.3 (H42 1st) X 2.3 (low range) X 4.11 (diff gear) = 40.64 crawl BJ42 4 spd NA spec
4.9 (H42 1st) X 2.3 (low range gears from '4spd' t/case) X 4.11 diff gear) = 46.31 NA spec
4.9 (H55F 1st) X 1.9 (low range) X 4.88 (diff gear) = 45.43 crawl (for comparision)
4.9 (H55F 1st) X 1.9 (low range) X 5.29 (diff gear) = 49.24 crawl (for comparision)
4.9 (H55F 1st) X 2.48 (low range) X 4.11 (diff gear) = 49.94 crawl

the advantage of the low t/case gear is your day to day driveablity stays the same, fuel milage does not change but when you go into low range your crawl has been increased by 30%...quite adaquate for most wheeling.
i was incorrect in my earlier post, the t/case swap is equivilant to changing the diff gears to 5.29...sorry

i also added another of my favorite swaps for the earlier 83-85 5 spd t/case, the gears from a 81-82 4 spd t/case will slip right in giving you a healthy 46/1 crawl. a 13% crawl increase...doesn't sound like much but you can feel the increase in torque off road.

I'm interested in this mod..
from the info I have found the low range ratio in my bj42 is 1.959:1.
What is the low range ratio in the HJ60 transfer (is it an A440 g/b?).

 

[tmarx]

...i also added another of my favorite swaps for the earlier 83-85 5 spd t/case, the gears from a 81-82 4 spd t/case will slip right in giving you a healthy 46/1 crawl. a 13% crawl increase...doesn't sound like much but you can feel the increase in torque off road.

Thanx for the valuable info and the fact that you have actually done it before .....

 

[Tapage]

What is the low range ratio in the HJ60 transfer (is it an A440 g/b?).

My Tencha come factory with H55F and 1.96:1 low gear set .. but autos ( A343 ? ) come with 2.48:1 as Wayne coment ..

 

[crushers]

glad to share...

i guess us back yard mechs are good for something after all...

Thanx for the valuable info and the fact that you have actually done it before .....

 

[brisveganbj42]

Yep, thanks for the valuable info on the gears.. now all i've got to do is track some down!.

 

[Diesel42]

Thanks Crushers. This is great info as i have always wanted to do some better gears but couldn't bring myself to the 1800.00-2000.00 Marks gear price tag. When the time comes to rebuild my t-case(83 BJ42 w/H55, I will follow your advice with the readily available gears. Awesome post.

 

[exmodlad]

Just for everyones info..i am parting out (2) split T cases that were behind 3B 4 Spd transmissions

Best Regards

Gord

 

[Hulsty]

is it only HJ60s that have a 2.488 low range? or do all 60 series autos with a A440F have that low range ? Does a 73 series share the same ratios as a BJ42 ?

4.9 (H55F 1st) X 1.9 (low range) X 4.11 (diff gear) = 38.26 crawl BJ42 5 spd NA spec

cheers This would definately help my 3F turn the 35''s easier!