How does a 4-speed compare to a 3-speed?

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Hi. My 73 FJ40 hangs at about 2700 RPM to go freeway speeds, and my carburetor doesn't like it. And neither do I.

How do 4-speeds do on the freeway? About what RPM do you guys run at (if you have the original motor)?

If anyone has had both, how do they compare? Is first gear lower on the 4-spd?

Thanks in advance for any info!
 
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And 1st gear is synchronized in the 4-spd. Kind of like this
Your carburetor is a wimp.
Haha. And yeah, I've got a brand new Weber that just isn't tuned very well because I don't know what I'm doing. I don't like it running so high for so long because I just rebuilt the whole engine and I want to take good care of it.
 
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If you want OD your going to need a GM auto trans+ conversion kit, toyota H55 5 speed manual or whatever US domestic 5/6 speed manual you can make fit with a conversion kit( if that's even possible). Plus different sized driveshafts.
 
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David70FJ40

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H55 here with 33" tires in my '70 FJ40 with the original 6.. At 60 in 5th gear I believe I see 2000 on the tach and the engine doesn't sound like it is straining. Once I get to a hill I have to downshift to 4th but that is no big deal to me. Also installed a split case from an 80's model LC as well.
 

Living in the Past

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So you're saying 4th is 27% higher than third gear on the 3-speed?
Didn't this answered other than early in the thread. Top gear is one to one in both. 73 model adding a four speed is easier then previous years. Find all the right parts could be a complete bolt in job.

To be clear Toyota used two different four speed in the 4X series. US got the H42 which first gear is around 3.5:1 which most markets got the H41 which first is around 5.0:1. H42 is a friendlier pavement which H41 have lower first for off road and low end torque for pulling.

H55 here with 33" tires in my '70 FJ40 with the original 6.. At 60 in 5th gear I believe I see 2000 on the tach and the engine doesn't sound like it is straining. Once I get to a hill I have to downshift to 4th but that is no big deal to me. Also installed a split case from an 80's model LC as well.

The H55F only uses the split transfer case. That creates it's own set of problems. The length is tight with a hand brake on the back to the torque tube. Then you need to source the hand brake which like the H55F was never imported to the US. Also if you want the shift cane in the same location finding the correct H55F top cover is difficult. Running a V8 a 60 series four or five speed top cover is a advantage.

There are also the Fairey OD that is NLA and only found second hand. Those require no mods other than changing parts in the transfer case. Plus the Hone that fits to the back of the transfer case. Again only available second hand and only works in 2WD.
 

David70FJ40

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The H55F only uses the split transfer case. That creates it's own set of problems. The length is tight with a hand brake on the back to the torque tube. Then you need to source the hand brake which like the H55F was never imported to the US. Also if you want the shift cane in the same location finding the correct H55F top cover is difficult. Running a V8 a 60 series four or five speed top cover is a advantage.
Ran into those problems. The tube was replaced, a parking brake from Street Rod Manufacturing was added, works okay, nothing special, had a hot rod shop alter the transmission cover to allow for the extra height in the H55 and the location of the shifter and had to drop the skid plate about an inch lower to allow for the size of the H55 and split case. On top of that was getting the drive shafts made and Tom Woods Driveshafts came through 100%. All-in-all, this was a tough modification, especially lifting the tranny and split case into position, but I would do it again given the results.
 
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Living in the Past

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Ran into those problems. The tube was replaced, a parking brake from Street Rod Manufacturing was added, works okay, nothing special, had a hot rod shop alter the transmission cover to allow for the extra height in the H55 and the location of the shifter and had to drop the skid plate about an inch lower to allow for the size of the H55 and split case. On top of that was getting the drive shafts made and Tom Woods Driveshafts came through 100%. All-in-all, this was a tough modification, especially lifting the tranny and split case into position, but I would do it again given the results.

Still waiting on a few items but other having to graft in a section from a 83 hump and figuring the fixed nuts for the crossmember L brackets everything else should be a bolt in on my 79. Hand brake will be on the rear axle. Got the driveshafts and bash plate worked into to the deal with a five speed and transfer from a BJ42. Already having to ship the T/T from Australia just made sense to get as much as possible. Bought my 79 off a friend years ago and always wished it was a 78 until lately. Going to a H55F gets easier the newer it is. From 78 to 79 was a big step. I'm happy to leave my 70 with the three on the tree shifter. Did a H42 in my 68 and that was enough work. Unless you want to keep a 40 original the H42 is a huge improvement over the the J30 three speed. Cost and work involved is much less to switch than a H55F.
 

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To be clear Toyota used two different four speed in the 4X series. US got the H42 which first gear is around 3.5:1 which most markets got the H41 which first is around 5.0:1. H42 is a friendlier pavement which H41 have lower first for off road and low end torque for pulling.
Although the H41 makes a nice street gear box too, if you are running 33" or larger tires.
 
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