[Hulsty]

Check my 85 model FJ73 with 4.11's and H55F, came with 1.9 ratio low range.

I'm going to try and put the 2.29 low range into my car with a fully manual 4x4 selector without the vac shift. The 2.29 low range gives me more reduction than if I fit 4.88 ratio diff centres.

[crushers]

the only thing that dictates what can be swapped is the idlershaft thickness...
the nice thing about the 2.29 (or the 2./48) is on the highway everything stays the same, once you go LOW then a whole new world opens up.

[Hulsty]

the 88 model would have the 38mm idler, my car and my spare box being 85 and earlier would be the 34mm idler shaft. Does this change anything on the gearbox? I was going to swap on the whole transfer case, remove the vac components and fit the manual operation body for 4x4 engadgement

[crushers]

the vac shifer has a different moulding than the manual so it won't be a direct bolt up. some mods will be required to change from vacuum to manual.
the case will bolt to the tranny with no issues.

[ozwallaby]

Originally Posted by crushers

the BJ42 5 spd comes with the 1.9 low
the BJ42 4 spd comes with the 2.3 low
the HJ60 auto comes with the 2.48 low

4.9 (H55F 1st) X 1.9 (low range) X 4.11 (diff gear) = 38.26 crawl BJ42 5 spd NA spec
4.3 (H42 1st) X 2.3 (low range) X 4.11 (diff gear) = 40.64 crawl BJ42 4 spd NA spec
4.9 (H42 1st) X 2.3 (low range gears from '4spd' t/case) X 4.11 diff gear) = 46.31 NA spec
4.9 (H55F 1st) X 1.9 (low range) X 4.88 (diff gear) = 45.43 crawl (for comparision)
4.9 (H55F 1st) X 1.9 (low range) X 5.29 (diff gear) = 49.24 crawl (for comparision)
4.9 (H55F 1st) X 2.48 (low range) X 4.11 (diff gear) = 49.94 crawl

the advantage of the low t/case gear is your day to day driveablity stays the same, fuel milage does not change but when you go into low range your crawl has been increased by 30%...quite adaquate for most wheeling.
i was incorrect in my earlier post, the t/case swap is equivilant to changing the diff gears to 5.29...sorry

i also added another of my favorite swaps for the earlier 83-85 5 spd t/case, the gears from a 81-82 4 spd t/case will slip right in giving you a healthy 46/1 crawl. a 13% crawl increase...doesn't sound like much but you can feel the increase in torque off road.

Crushers, shouldn't the 4spd low range line read 4.9 (H55F 1st) at the start or am I mistaken?

[crushers]

corrected: (thanks)

4.9 (H55F 1st) X 1.9 (low range) X 4.11 (diff gear) = 38.26 crawl BJ42 5 spd NA spec
4.3 (H42 1st) X 2.3 (low range) X 4.11 (diff gear) = 40.64 crawl BJ42 4 spd NA spec
4.9 (H55F 1st) X 2.3 (low range gears from '4spd' t/case) X 4.11 diff gear) = 46.31 NA spec
4.9 (H55F 1st) X 1.9 (low range) X 4.88 (diff gear) = 45.43 crawl (for comparision)
4.9 (H55F 1st) X 1.9 (low range) X 5.29 (diff gear) = 49.24 crawl (for comparision)
4.9 (H55F 1st) X 2.48 (low range) X 4.11 (diff gear) = 49.94 crawl

[Hendrik]

All good info. Thanks v much.