Gearing Question 34 x 10.50's

[MAINEFJ40]

I know there have been many discussions about gearing in 40's I am unable to find anything that suits my needs or answers all of my questions. I have a 74 FJ40, with 4"lift, 34 x 10.50 TSL's 1F engine with 4 speed and stock transfer, I currently have stock gearing. I just ordered an aussie locker for the rear and before I install I wanted some opinions on differential gearing. Is the stock gearing (4.11 I think) going to be ok with my set up. The only performance mods to the engine are a header and weber carb. I have not ran this truck yet with the 34's so I am unsure how it goes.

Thanks for any input guys, I am sure someone out there has a similar set up.

 

[Brian in Oregon]

I'm doing 2800 rpm at 60 mph with 33" tires.

I have more power than the six, and I can tell you that at 4000 feet on 6% grades with four people and a lot of camping gear that I would not want to go to 3.70 gears. If I was in flat country, sure.

 

[MAINEFJ40]

I definately would not be going with any taller gears, I was wondering if I was going to need any lower gears for trails and steep climbs off road.

 

[MOfj40]

I'm running 3spd tranny and case behind F, 4.11s with locked rear turning 33.x10.50s. Most of my offroad time centers on steep climbs and trails in the Ozark Mtns.

For climbing, it's great. The F/2F lugs so well that I've never had a problem. If I want to crawl up I'll keep it a hair above idle and it climbs great.

Downhill's a different story. I end up riding the brakes the whole way because the gearing is too tall. However, I don't think changing the ring and pinion will help- not enough difference. A significant increase is gearing - transmission or Tcase is needed to really slow you down.

 

[matt.mcinnes]

I run 4.56's these suit taller tires better than the 4.11's in my opinion.

1st Low is better down steep hills too

 

[Josie'sLandCruiser]

Hi All:

X2 on the 4.56 R&P gears for 34 inch tires.

The 4.11s will work, but the 4.56s will help get the engine back into its powerband. The 4.11s offer a bit of an overdrive at highway speeds, but off-road the 4.56s will be appreciated.

Regards,

Alan

 

[MAINEFJ40]

Maybe I would better off leaving the diffs alone and doing some gearing mods in the transfer, what do you think. If the 4.11's are good on the highway and decent offroad I think I will leave the diffs alone for now and see how it does. Any recomendations on transfer case gearing i.e. where to get them and what to run.

 

[shelfboy1]

ive run 411s with 36s ,38s and 40s on, off road, up hill, down hill never had a problem .also have disk brakes and 2 fs never had a power problem in the deepest mud or the steepest hills .on 2 trucks we run a 3 speed case with 4 speed and it does help down hills .also the lower gears work well when we chain up the 38s and breakages are few even with lockers good luck

 

[MOfj40]

Depends on how much you want to spend. The quick fix is buy a toybox or orion t/c and slap it in. It's not cheap, however.

The cheaper mod is to install a SM420 or SM465 transmission (7:1 and 6.?:1 1st gears, respectively). However, you'll have to spend few hundred on an adapter to the landcruiser t-case and do some minor adaptations to the transmission input shaft. There's a ton of valuable info in the tech links.

Both are popular mods. NV4500s and Dana 300s are also popular, but not as widespread.

 

[mr_manny]

a NV4500 with an orion

 

[Mark W]

How do you use the rig?

If it is a daily driver that sees a bit (even a good bit) of off road time on the weekends, then your 4.11s will probably serve you better than anything steeper.

a "3 speed T/C" will give you lower gearing for off road use. By the same amount as swapping 4.88s into the diffs. For a reasonably priced mod, that would be my first step if it was my rig and it was used as I refer to above.


Mark...

 

[MOfj40]

a NV4500 with an orion

That would be my ideal setup as well. However, purchasing and installing those two items would cost me more than my total investment in the 40 thus far, so I won't be pulling the trigger on that any time soon.

 

[MAINEFJ40]

Well I think from recomendations and doing some research the Orion looks like the way to go. I will probable wait until next years budget before I go with it. Anyone seen any used ones out there? I doubt it but I suppose I will keep looking. What is the designation for the factory 4 speed transmission?

 

[MAINEFJ40]

Vendor for the Orion? Any other mods that should be done at the same time? I think I till stay with the stock 4 speed tranny.
Thanks for all of the info. At this point I just can't wait to get it on the trail.

 

[Letsgomoreplaces]

4.56 for 34"

4.56 will work well w/ the 34"s

 

[dirtcurt]

I know there have been many discussions about gearing in 40's I am unable to find anything that suits my needs or answers all of my questions. I have a 74 FJ40, with 4"lift, 34 x 10.50 TSL's 1F engine with 4 speed and stock transfer, I currently have stock gearing. I just ordered an aussie locker for the rear and before I install I wanted some opinions on differential gearing. Is the stock gearing (4.11 I think) going to be ok with my set up. The only performance mods to the engine are a header and weber carb. I have not ran this truck yet with the 34's so I am unsure how it goes.

Thanks for any input guys, I am sure someone out there has a similar set up.

I have this same setup(1974) and did the 2.31($200) transfer with the Non-USA 4 speed($500) and am running 33x10.50x15 tires with 4.11 diffs. It's an OK trail setup at 48 to 1. I still need the park brake (about 2 clicks after contact) on super steep downhills. Uphill is fine, actually close to great, flat huge boulder strewn trail is most difficult, but not impossible. Highway hillclimbs are all about how much HP engine is putting out. Lower gears in most cases will not help heavy loads uphill on the highway. You will do it in either 3rd or 4th and be at the mercy of your total HP engine produces and rpms you willing to wind. 4th is better for the trans(straight through no gear reduction). When I'm medium loaded, it will just pull 4th with an occasional 3rd gear run on the 6% grade with the same speed on speedo and GPS. Put the trailer behind and alot of 3rd to maintain 45-55mph. Light loads will pull that same hill in 4th(50-55 mph actual) with no problem. I get 3,100 RPMs at 70mph and that is not really great for long runs at that speed at 100 degrees air temp. I check speeds and distance with a GPS. Speedo shows 58-60 MPH at 70 MPH actual speed. My halfbreed 1f-2f has a header and KN with a non-USA dizzy and .020 bored engine and fan clutch. I have no idea how much my loads weigh. Hope this helps.

 

[Mark W]

Well I think from recomendations and doing some research the Orion looks like the way to go. I will probable wait until next years budget before I go with it. Anyone seen any used ones out there? I doubt it but I suppose I will keep looking. What is the designation for the factory 4 speed transmission?

An 4:1 Orion behind an H42 is fine if your off roading is all crawling. But with 4th gear low range lower than first gear high range, most trails other than actual obstacles are too fast for low range and often too slow of high range.

I love the 4:1 Orion with a 203 in front of it, but I found it less than ideal when I was running it alone behind the H42.

Again,if all you do is crawling, then this is not a problem.

A 3:2 Orion would be a horse of a different color.


Mark...

 

[JJS]

I had an H42 with 4.11's and 34" TSL's. The truck could pull a house down...well, with the SBC, anyway.