Help with 1 ton axle choice for fzj80 build

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I guess one just needs to relocate the fuel tank to the rear behind the axle to make the toybox work.


In the process of figuring out the best means of doing so, :D. A Marks Crawl box or the above mentioned setup is so necessary at this point.
 
The pattern is not the same. The two transmissions have different rear case adapters, but it looks like one might be able to remove the the rear adapter and output shaft from a 62 series and put it on the 80 series tranny. It looks like it can be done without opening up the whole transmission. This is from the info I deduced from the EPC. My understanding is that the splines are the same, just the shafts are shorter as the 80 series t-case does not have the thru shaft. I have email to Rodney, to see if it can be done.

If so this would open up the options for the toybox and converting to a part time case as well. I guess one jus t needs to relocate the fuel tank to the rear behind the axle to make the toybox work.


Please let me know how this goes! I've been saying this for over a year, but I don't have the resources or the know-how to pull it off. As for the relocated fuel tank, just use a factory (or aftermarket) sub tank that goes behind the rear axle and use it as a main tank. That's the easy part!
 
i called and spoke at length with downey about this MC
Downey Off-Road

it is off a one ton t100. an actaul asain/toyota part. great price too. only problem is that according to the tech guy at downey the t100 mc is only 1 1/16 whereas the 80 series mc is just slightly smaller at 1". the tech didn't think i would see much diff with the downy MC. he suggested i block off the port on the 80 series mc where the abs line returns to the MC. after i block off the ABS return line I can reevaluate my situation.

anyone know which line on the MC i should block off to disingage the ABS.
i just want to toss all that abs assembly mess and have one line from the MC to the rear brakes and one line on the MC to the front brakes. simple. if i can get it figured out to this point i can easily go with the gm MC if needed.

No ABS on the Downey 1-1/16", and that extra 1/16" made my disk/drum setup feel seat of the pants 100x better. 4x lockup with either set of tires, any surface and no more double pumping.
 
Have any of you guys ran an auxilliary tank as the main tank on their DAILY DRIVER? I dont want to ruin my reliability since i drive my 80 everywhere! what is involved to run the auxilliary tank as the main tank? Electrical is my weak point, how much wiring is invloved?
 
finished rebuilding the tcase with the marks gears today. not a simple job. i could do the next one in a fraction of the time.

key difficulties of the job:

the marks instructions are vague in several places. the most frustration is with where to cut the case to fit the larger gears. it is necesary to trim the oil shield slinger thing as shown in my pics. you also need to make one cut to the aluminum case itself like shown.
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those that fantisize about making a lower gearset for the 80 case should stop. you cant get a larger low gear in the case. it wont fit.

this first pic shows the 2.45 low gear sitting atop the installed 3.1 low gear. not much difference

but enough that it barely fits in the case

the last pic is of the shift fork shaft support hole. of the low gear gets any larger that the marks 3.1 gear it will compromise this shaft support
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question

i did not rebuild my tcase. i rebuilt a supposed lower milage/less beat apon tcase. but the tcase i rebuilt has more endplay in the front extension housing. (ie the flange where the front driveshaft mates)

my old faithfull tcase had little endplay in the front extension housing but the used unit i baught has alost 1/8" endplay. i could easily swap my oldfaithful front extension housing if needs but if others have noted to have a little endplay in their front extension housings i will leave mine alone

so do others have some endplay?
 
Dustin, If it is easy to swap out, d it for the piece of mind. Give me a call when you want to install it. At this point, better count me out of the run this weekend. I need to secure something before I can spend money on gas for fun.
 
just an update

finished installing the tcase last pm. the lower gears make no more noise than the oe gears. seem to work flawless. the added lowness feels good. im taking her up to bald mountain (shaver lake tonight) and will wheel the weekend. will take pics.

if anyone wants to come up and hang out pm me. (frizerly???)
 
Can you really feel a difference?
 
I see that the transfer case differential is still installed....Why did you not change the case over to a part time unit while doing the re-gear?



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Dustin and I had a long talk about this during the earlier stages of his build. I brought up better gas milage, vibration issues, and he wanted the ability to be able to run the front and rear locked and still have the center diff allow for turning since it can spin the 2 drivelines at different speeds.

I had the opportunity to help him pull apart the t-case and install some of the gears. This was the first time we both saw the internal working of his t-case. They are an incredible work of art and Toyota know how. Not only does the T-case allow for 4 wheel drive and high/low options, but with the center diff, the tire drag and hop when turning doesn't happen.

If he removed the center diff, wouldn't he make his rig harder to turn with both axles locked up? Is there information on how to remove the center diff?
 
i can feel a difference. 25% lower is undeniable. it aint no crawler though

i left the center diff in because i didnt want hubs. one more thing to break. im running solid flanges.

the tcase worked perfectly. i broke the trail up to bald mtn sat. me and my cousin went solo to the trail and met up with 6 minis. the snow was real deap in places. the minis were in front for about a mile but we were not moving. eventually the minis got out of the way. big tires and horsepower prevailed. i love this truck. i bounced off the rev limiter repeatedly and the truck didn't care. never got hot and tranny light never came on. i recommend the gears

YouTube - Fun in the snow

more pics later

in defence of the minis patrol none had bigger than 37's and were limited by that puny 22r. (im ready to take some hits for that) the mini team were a great bunch. they snatched me out repeatedly after i would fall in some hole or push myself too far into the snow. they had a batchler party at the top. i love my new 4" arb snatch strap.

justin and his wife from visalia came along in their built 91 fj80 after a while. and jon, a cool guy from the forum also came along in his late model, diamond axled, 37 mtre'd, dual cased 2.7L tacoma also brought up the rear. Jon's truck is killer and unstopable.
 
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Glad you like them and working out well. Nice video! Your 80 looks good. What's up with the front fenders?
I never run my crawler in snow. It never felt a good match. To me running in snow is all about horsepower and wheel speed.
 
Glad you like them and working out well. Nice video! Your 80 looks good. What's up with the front fenders?
I never run my crawler in snow. It never felt a good match. To me running in snow is all about horsepower and wheel speed.

fenders are on the way. ive put them and bedlining the sides on the list for after i mount the winch

the minis do great with their crawlers most of the time but they arn't so heavy as the 80. i prefer hp and speed for snow when poss. just stop before the wheels sink
 
the first pic is of my cousin paul who did the vid. the last pic is of my truck running this same trail 2 years ago-not a scratch on her then. i wouldn't dare bounce her off the rev limiter then. but i dont think she minds. the 1fzfe is a fantastic engine and if maintained i believe almost indistructable. note that on this run the adjustable boost controller was limited to 4 lbs boost. egts stayed at 1400 or less.
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i left the center diff in because i didnt want hubs. one more thing to break. im running solid flanges.



You did not want to have lockouts.... I can understand that if you are going to be working your truck.



I am currently building a 1997 LX450 for a customer and I have the transfer case out for a part time kit and the Marks gears, among many other things.


Looks like fun!

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