FJ40 1974 - 1978 Transmission Hump 4-Speed Conversion Fiberglass

Ackcruisers

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Has anyone installed a fiberglass FJ40 1974-1978 Transmission Hump for their 4 speed conversion? My 1976 South American truck came stock with the 3 speed. I'm upgrading to H42 and need to modify the gear shift holes to accommodate the 4 speed. I do not want to modify a perfect condition 3 speed transmission hump. Any opinions good or bad on these fiberglass versions would be helpful.

JT Outfitters offers one for $199. Link is below.


 
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Since you have a non-US truck, you might try to verify if that 4 speed cover will correctly fit your floor panm especially around the back end (rear). I ended up having to do a 1" body lift on my '65 FJ45 to get the 3 speed trans tunnel cover to clear the 4 speed gear box. I also drilled it for the shifter. The 4 speed trans. is taller than the 3 speed and having the tunnel cover rest on the transmission created an ungodly amount of noise that was eliminated when I lifted the body 1".
 

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Thanks @SteveH. Appreciate the detail about the height of the H42. I hope I do not have to lift the body tub to avoid the noise of the cover plate hitting hump. According to another thread, my 1976 3 speed hump height matches the height of the 4 speed hump. More details on this topic can be found here.

1627602891218.jpeg
 
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Since you have a non-US truck, you might try to verify if that 4 speed cover will correctly fit your floor panm especially around the back end (rear). I ended up having to do a 1" body lift on my '65 FJ45 to get the 3 speed trans tunnel cover to clear the 4 speed gear box. I also drilled it for the shifter. The 4 speed trans. is taller than the 3 speed and having the tunnel cover rest on the transmission created an ungodly amount of noise that was eliminated when I lifted the body 1".


Floor changed 9/72 because that is when some markets got the four speed in the FJ40. US was around the start of 1974 in the US but in Australia, largest market for the 40 series it started over a year earlier. It is also when the torque tube behind transfer case changed shape and move a little further back. Both changes make switching from three speed to a four speed much easier.

In spring of 1994 I went thru all the work of adding a four speed to my 68. 68 is basically the same as a 65 so well aware of the challenges of installing a four speed in a pre 9/72 FJ40. I did not do any body lift. I used a later four speed transmission hump trimmed in the back. No tub or frame mods were needed. Ironically in July of 1994 out of the blue someone offered me a 73 FST for price to good to pass up. Few months earlier and the 73 would have had the four speed installed.
 

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Thanks @Living in the Past I just measured the H42 and from the top plate to top of shifter it’s just shy of 4.5 inches. The J30 3 speed measures 4 inches from top plate to bottom of transmission hump. There is plenty of room for the H42. Attached image of the rear of the transmission hump. Only modification appears to be the diameter for the hole for the transmission shifter. Once 4 speed is in, I’ll post images.
739C1C41-54EE-4162-B444-BF7CB7237D8D.jpg

760470D3-FE6B-4E90-AA7F-2BD08F577FE0.jpeg
 
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Took these pictures about a year ago and height of my 2/73 is same as the 78.
IMG_20200817_092024709.jpg

IMG_20200817_091455374.jpg

I'll be using when I convert my 73 to a four speed. Well be using four speed driveshaft I already have. Flange patterns are the biggest issue I will have to deal with. Your later seventies should already be the same.
 

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