Hello Guest

Transfercase elimination

  • 14 Replies
  • 2529 Views

0 Members and 2 Guests are viewing this topic.

Transfercase elimination
« on: May 23, 2008, 03:45:04 PM »
I have a bone stock 1990 Sammy.
I did a search but did not find it discussed.
This is to be strickly a daily driver to work and back. 20 miles per day. I live on the gulf coast of Florida and it is all flat. I have no intention of 4-wheeling it anywhere in the near future anyways.
Although I might take it to Murpy, NC some day if I own it long enough.

Without driving it upside down while hanging out the door...........does the transmission output rotate the right way to turn the rear axle?

Assuming it does, has anyone ever removed the xcase and replaced the two driveshafts with one long driveshaft?

If I did do that, I know it would be force the engine to work harder, but would it be a total dog?

Thanks in advance

*

Offline johngat

  • 5
  • 0
  • Gender: Male
Re: Transfercase elimination
« Reply #1 on: May 23, 2008, 03:59:43 PM »
This may not be an option for You but , You could use the "dummy" Tcase out of a 2wd model . I have seen a couple of them for sale recently is the only reason I mentioned it .
'87 Sami , 3" Calmini lift , Currie tow shackels up front , 2" longer in the back , 6.5 to 1 Tcase gears , RRO Mega mount Tcase mount , Weber Carb , Trail tough ott steering .

*

Offline RHodge

  • 523
  • 0
  • Gender: Male
Re: Transfercase elimination
« Reply #2 on: May 23, 2008, 05:35:59 PM »
I don't think your going to gain anything buy doing that , your still going to have the frond diff you'll be pushing around, and the case doesn't weigh that much, plus the read drive shaft will be at a weird angle. If your concerned about milage I would just put a good set of highway tires on it and call it good


*

Offline 83sj410

  • 46
  • 0
  • Gender: Male
Re: Transfercase elimination
« Reply #3 on: May 23, 2008, 06:16:27 PM »
Also you would lose the gear reduction of the t-case and your gearing would be too high and you would end up driving in fourth gear everywhere.That would probably nulify any mileage gains from the loss of the t-case.
Who knew 45 horsepower could be so fun???

Re: Transfercase elimination
« Reply #4 on: May 23, 2008, 07:31:28 PM »
I haven't looked into how Suzuki's t-case is set up, but most normal cases are 1:1 ratio in two wheel or four wheel high, so reduction would not be an issue. About the only gain you would get is losing the extra weight of the transfer case and front driveshaft and maybe a little less friction of not having to spin as many gears. Not going to make that big of a difference in fuel mileage to justify the expense.

*

Offline Hillbillydave

  • 213
  • 1
  • Gender: Male
Re: Transfercase elimination
« Reply #5 on: May 23, 2008, 08:14:55 PM »
If I'm not mistaken, the output through the transfer case is about 1.4 to 1, so it would be higher without the transfer case. My advice would be to run the stock size tires, 205 70 15, I think, and it should get 20+ mpg. You might look for ways to lighten it up: remove the rear seat, use a ragtop, even remove the front driveshaft. The dummy tcase sound like a good idea, if you could find one, but the front gears would still be there, so you would need the front axle from a 2wd as well.
'89 sidekick 1.3L 3" blue suspension parts, custom strut extensions 31x10.5 Mud Trac's on 10" rims rear fenders trimmed, lincoln locked rear, Rochester Carb on custom adapter
93 Sammy project, SPOA with 34's, 5.12's, welded, in the works

Re: Transfercase elimination
« Reply #6 on: May 24, 2008, 09:40:18 AM »
Thats interesting that the sammy's do not have a 1:1 ratio in the tcase, also are manual locking hubs not available for the sammy's? This would eliminate spinning the front diff gears. I have a 'kick, so Im not familar with the workings of a Samuri. I did find out on my 'kick that when the transfer case is put in neutral, both front and rear driveshafts are locked together, even though it disconnected the input from the transmission. I'm finding out the Japanese do things a little different than what we do over here. All of my previous 4X4's have been US made.

*

Offline Jeremiah

  • 1880
  • 1
  • Gender: Male
  • Viva La ZUKIWORLD!
Re: Transfercase elimination
« Reply #7 on: May 24, 2008, 09:54:42 AM »
The transfer case has a built in reduction, it's not 1:1. The front diff is only engaged when in 4WD - and yes they're manual locking hubs.

What's the point of removing the transfer case?
'96 4 door kick: 29" Pep-Boys M/T, 1.5" OME
'83 SJ410: 31" Toyo M/T, SPOA, 1.3L
'08 Yamaha FZ6

Re: Transfercase elimination
« Reply #8 on: May 24, 2008, 09:58:45 AM »
My point exactly.

What's the point of removing the transfer case?

*

Offline Uncivilized

  • 1469
  • 1
  • Gender: Male
    • Car Domain
Re: Transfercase elimination
« Reply #9 on: May 24, 2008, 10:20:19 AM »
Sounds like a lot of work with little to no gain. I didn't think you'd need to worry about fuel milage in a stock samurai....

*

Offline Jeremiah

  • 1880
  • 1
  • Gender: Male
  • Viva La ZUKIWORLD!
Re: Transfercase elimination
« Reply #10 on: May 24, 2008, 12:31:08 PM »
You'd be better off selling your sami, and buying a tracker / sidekick for a daily driver. The Trackicks get better gas mileage, better suspension, more room...

Samurai's are harder to find, so they sell for more money than a used trackick. I sold my sami for $3200, and got a kick for $1900.
'96 4 door kick: 29" Pep-Boys M/T, 1.5" OME
'83 SJ410: 31" Toyo M/T, SPOA, 1.3L
'08 Yamaha FZ6

Re: Transfercase elimination
« Reply #11 on: May 24, 2008, 04:42:49 PM »
Yea I was having a "what if" moment.
I forgot the axle input shafts are inline and offset from the crank. It is usually a no-no to run a driveshaft at an angle sideways as well as up and down.
The transmission has pretty much standard gear ratios for vehicles running without a reduction transfercase. I imagine the only reason for doing so in the Sammy was to be able to run the anemic 1.3 versus more cubic inches. Forcing the 1.3 to run 30% higher rpm's instead.

Did the 2-wheel drive sammy run a straight axle in place of the driven axle or did they install independent suspension? Did they go the cheap route and just installed a tube axle on the 4x4 springs and reuse the same steering, shocks, etc.? If so then running the front axle unlocked would be virtually the same except for a few more pounds.

Another way to get to a 1to1 4th gear input to the rear axle would be to install a 2.70 ring and pinion.

Like I said, it is pure stock now, including the wheels and tires. I am just thinking of stuff to change just to see if it would work. Anything I might do would be 100% reverseable and undetectable upon reversal.

*

Offline ack

  • 1659
  • 34
  • Gender: Male
  • Professional askhole
    • Ack's FAQ
Re: Transfercase elimination
« Reply #12 on: May 24, 2008, 10:09:19 PM »
To answer your questons, The 2wd Samurai is set up exactly as the 4wd Samurai with the exception that the 2wd transfer case only provides 2-high gearing to the rear driveshaft, there is NO front output shaft and the front axle is an empty tube with the birfield-style kingpin-and-hub arrangement on either end.

For specific details, download the '90-'92 Supplement (.pdf file) to the Samurai Factory Service Manual at Ack's FAQ. The link is in my signature below.  Do a search for supplement.

Overall, the best way to get good mileage out of a Samurai is a thorough overhaul of the carburetor/throttle body, properly inflated tires, regular oil changes and regular tuneups like any other vehicle.

Cleaned-up locking hubs run in the unlocked mode would help too. And removing the front driveshaft... but then you are screwed when you get stuck in sand.

Oh, and be prepared to get your Engine Control Module (ECM) rebuilt. They can go bad but fortunately there are folks here on the 'net that can fix them for you.   

All the mods that we as offroaders do are not designed to get better mileage - that's just a natural bonus when compared to other larger trucks.
« Last Edit: May 24, 2008, 10:21:58 PM by ack »
Ack

'88 Samurai, '88.5 Samurai TT, '11 Ford Transit Connect XLT
Ack's FAQ  http://www.acksfaq.com

*

Offline Skyhiranger

  • 3734
  • 122
  • I don't buy, what I can build
Re: Transfercase elimination
« Reply #13 on: May 26, 2008, 07:46:31 AM »
Yea I was having a "what if" moment.
I forgot the axle input shafts are inline and offset from the crank. It is usually a no-no to run a driveshaft at an angle sideways as well as up and down.
The transmission has pretty much standard gear ratios for vehicles running without a reduction transfercase. I imagine the only reason for doing so in the Sammy was to be able to run the anemic 1.3 versus more cubic inches. Forcing the 1.3 to run 30% higher rpm's instead.

Did the 2-wheel drive sammy run a straight axle in place of the driven axle or did they install independent suspension? Did they go the cheap route and just installed a tube axle on the 4x4 springs and reuse the same steering, shocks, etc.? If so then running the front axle unlocked would be virtually the same except for a few more pounds.

Another way to get to a 1to1 4th gear input to the rear axle would be to install a 2.70 ring and pinion.

Like I said, it is pure stock now, including the wheels and tires. I am just thinking of stuff to change just to see if it would work. Anything I might do would be 100% reverseable and undetectable upon reversal.


The 2wd samurai front axle has the same type knuckles on it that a 4wd axle does.  But instead of a diff in the center, it has one long solid tube.  They use the same shock setup, springs, steering, etc.

Just put yours in 2wd, turn the hubs out and drive it......you'd spend  more in swapping stuff around to eliminate your front axle and tcase than you would ever gain back in fuel savings (and I wouldn't bet you would get any better MPG).
Samurais get upper 20s for MPG....that is very respectable for a 4wd vehicle that is as aerodynamic as a box (IMO).
Tracker and Sidekick parts for sale.....PM me with your wants/needs.

*

Offline mrfuelish

  • *
  • 2862
  • 13
  • Gender: Male
  • you must have a perception problem.
Re: Transfercase elimination
« Reply #14 on: May 26, 2008, 03:03:37 PM »
ya if you put in a 2.7 ring and pinion you would only need first and second gear.  8)
1987,1988,1988,1990 samurai's,  1953 m38a1,  1996 x-90,blue.1996 x-90 red.1994 2 door tracker.   only Dead Fish go with the flow.                No Hairy Nosed Wombats were ran over on the trail today.       My ZUK is Xenophobic.