5 SPEED TRANSMISSION CONVERSION ON A 1977 FJ40

IZZYDUSIT

Adventurer
Hi there,
I need some information about doing a 5 spd trans. conversion on a FJ40.
looking for some cost, availability, and issues on installation from those of you whom went through this rout.
any information on this subject is appreciated!
thank!
 

nickw

Adventurer
There are others that surely know more than myself, but the major issue your going to have is the Tcase/Parking brake. With the 5spd you need a split Tcase, split Tcase does not have a parking brake like your current Tcase. Options are:

1) Retrofit aftermarket parking brake to split Tcase. Based on my research there is no clean/sano way to do this. The aftermarket options look like hobbled together go-kart brakes or something off a mountain bike from 1993. Seem to work OK, but just doesn't seem like the best solution to the problem.
2) Later model 40's (I think post 79') had a factory split Tcase with the parking brake on the rear axle. So a rear axle upgrade would also work, just more $$ but OEM which is nice. Maybe another $3k?

I couldn't accept option 1 and wasn't willing to drop the extra dough on option 2. If your NOT keeping the stock engine, other options I looked into were:
1) Convert to 700r4 auto tranny, keep stock Tcase/brake.
2) Use Ranger OD, keeps stock tranny/Tcase. Probably the cleanest/best bang for your buck route, but some say it's noisy.

Based on years of research, I came to the following conclusion:
1) Keep the damn thing stock and stop trying to make a FJ40 something it wasnt. YMMV.
 

Jonathan Hanson

Supporting Sponsor
An H55 on an FJ40 results in a very short rear driveshaft, and some interesting driveline angles at full droop, especially if you have a lift.

Consider instead installing an H41 transmission (lower first gear) and 3.70 diffs. You wind up with a more or less stock low range first, and slightly lower highway RPMs.
 
I agree with Mr. Hanson, and with the addition of a 33" tire, you should be able to cruise relatively comfortably. Send a PM to member 1911 as I believe he has this exact setup and his Cruiser is a pleasure to drive.
 

Fantom

Observer
One of my good friends had a 40, originally with a B engine and 4 speed, upgraded to a 3B and 5 speed (H55).
Not cheap to do, but way better than the alternative. In your case, to gain an extra gear, I don't know if it will be worth it.
In his case, the driveshaft for the back was short, but nothing weird, but, he has a 3B, not an F engine. The e-brake issue is valid, but these day there are T-Case brake options available for around $200-250, and they work well. The cost of the transmission would probably be the biggest issue, unless you have access to one at a good price.
The main question would be why? extra highway gears? or something else? is it really worth it?
 

Skrewball

Observer
the rear driveshaft length isnt an issue with the 5 speed and split case.

the TSM e brake option works well, but doesnt fit well. to fit it under the 40, you have to mount it low on the transfer case. connecting the cable to the ebrake is not the easiest thing to do.

with the multiple 5 speeds i have installed, they are nice, but not the golden fix for highway rpms. they reduce the cruising rpms by about 500. depending on the other gearing that could be substantial for an f engine.

taller tires and stock gears, with lower gear options for low range is a direction i would go.
 

BreckBJ44

Observer
Issues:
You need a 40 specific h55 (top cover is different from a 60 series h55).
You need to find a F/H series h55. Some are B series and have a different input shaft.
Rear Brake Issue - Post 1981 fj40 axle in the rear would fix this. There are some split transfers with a transfer output brake, but they are rarer than the 40 series top cover plate)

Notes:
Driveshafts are not a huge issue as toyota did this stock. If you have an extreme lift, you may have to go custom double cardan and long travel.
the H41 and H55 have the same gearing in the first four gears. Source whatever you can find and get 3:73s (which would come with it if you just do a post 8/80 FJ40 axle swap). Either way, your first gear is a stupid low 4.8:1 and your 4th is 1:1. the 5th is a bonus.

Send me an email if you are ready to pull the trigger as I have a source with a few h55s (both B and F/H) and I have a set of 8/80 and later BJ44 axles with 4:11s/parking breakes in them for sale. They are non-usa so have the stock 4:11 over the 3:73s that came in the ones here. I could sell them diffless too if you wanted.
 

cruiseroutfit

Supporting Sponsor: Cruiser Outfitters
Love my H55F, installed it into my SOA 40 over 10 years ago, never a hitch. Couple of thoughts. I didn't have to use a different top cover, rather I modified my trans cover using a 60 series trans/t-case cover and boots for a nice clean look. Also, I installed a floor mount park-brake handle rather than the dash unit, I'm a big fan of the added mechanical advantage and easy of use. Lastly, I'm using the rear axle with the park brakes, they can be had for $200-300, worst case would be $400-500 for the complete axle and not only are the working brakes far superior but the park brake is that much better too in my opinion. Single wheel cylinder (plus), self-adjusting brakes (plus), bigger shoes (plus) and better parts availability (plus, they are the same as any 80-94 semi-float LC axle parts so easy to find). If your serious about keeping the t-case mounted park brake, you will lose some rear drive line length but they are available 100% OEM just as your current t-case system.

I don't need to go on about the benefits of the 5 speed itself, but its worth mentioning that the split-case mated to most (like 99.9%) of H55F's is a superior t-case that is very stout, shifts nice and excellent reliability. There is a super rare H55F that mates to the 1-piece case, so rare I've not see one in person, just a picture.
 

General Automag

Adventurer
I too would like a 5-speed or some other way to get a higher highway speed with lower engine rpms. We have a stock '71 FJ40 with the F engine and 3-speed transmission. I'm told by several very reputable Land Cruiser shops that it's just not worth the money and trouble due to all that is needed to make it work. I know that anything can be done with unlimited funds, but I believe these guys when they say it's not really practical.

When we first got our '40, it had 27" tires. I moved up to 33's with a shackle lift and brought the "highway cruising" speed from 55mph to about 60-62 mph without winding out the engine too much. After reading this thread and looking at a 5-speed or overdrive option, I'm now considering 35" tires. Can anyone show me the calculations to figure out engine rpms and cruising speed based on gearing and tire size? Our trans and axle gears (4.11.1?) are stock. I'm not sure how 35's would look on a stock rig though.

It just seems like it takes forever to get somewhere, and with the bench seats, the heat, and no A/C, it just makes you want faster than 60mph. Just to make myself feel better about driving the old Cruiser on longer trips, I ran the numbers:

For a 250-mile trip, I calculated the following times:
55mph = 4 hours, 33 minutes
60mph = 4 hours, 10 minutes
65mph = 3 hours, 51 minutes
70mph = 3 hours, 34 minutes
75mph = 3 hours, 20 minutes.

I wouldn't drive an FJ40 really much faster than 70mph anyway, so if you did have an overdrive or 5-speed transmission or taller gears, you would get to your destination 36 minutes faster, or said another way, for every 100 miles on your trip, you will get there roughly 15 minutes faster by going 70mph versus 60mph. Since you only can drive 70+ on interstates or highways, this makes less of a difference if you are not on these roads. Anway... let the Forum know what you come with.
 
the H41 and H55 have the same gearing in the first four gears. Source whatever you can find and get 3:73s (which would come with it if you just do a post 8/80 FJ40 axle swap). Either way, your first gear is a stupid low 4.8:1 and your 4th is 1:1. the 5th is a bonus.

However, in all North American Landcruisers with 4 spds the H42 was stock with a mere 3.555 1st gear.

Charlie
 

Hoosier 45

Adventurer
It is funny to think, back in about 1988, a buddy and I drove my 1977 fj40 from Indiana to LA via the grand Canyon and back in 10 Days we only passed 2 vehicle on the WHOLE 5000 mile trip, to get the best mpg we could, we drove looong streaches at 45 -50.

About 4 years later my new wife and I drove the same beast to Idaho and back on our honey moon. Looking back I guess it was kinda nuts. ah but those were the days! I still have the wife and many parts of the 40 are now transplants in the 1965 fj45 pick-up.
 

Jonathan Hanson

Supporting Sponsor
I'm now considering 35" tires. Can anyone show me the calculations to figure out engine rpms and cruising speed based on gearing and tire size? Our trans and axle gears (4.11.1?) are stock. I'm not sure how 35's would look on a stock rig though.

Rather than worrying about how 35s would look, I would be concerned about how they would perform. You'd almost certainly run into clearance issues without more lift and/or fender trimming. More importantly, 35s are on the edge for the stock birfields. If you go from 4.11 diffs to 3.70s, you gain drivetrain strength. Installing ever-larger tires loses drivetrain strength.
 

JohnnyS

Explorer
H41, 3.70s, and keep your 33s....
None of my 40s have ever been fun at over 65.
I maxed my 76 FJ40 out down some big hills (Black Canyon on I-17 being one) and it was freaking scary; I was much younger and dumber.
 

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