Davo_60 (ACT) replied:

I think the 4.5 has the H151, and yes it is far stronger, totally different design. 5th gear is part of the main cluster i thnk so the box has so should be fine for towing. Also has internal oil pump and is physically larger.

Member - Phil G (SA) replied:

Yep, like Davo said. The diffs are the same though :-(( but I think they are a different ratio.

Plenty of auto FZJ105s around if you're interested in a change.

V8Diesel replied:

I've got a petrol 105 and I reckon it's a beauty. They go like stink and have huge reserves of torque. I just climed a steep dirt hill a few days ago towing a tandem trailer grossly overloaded with rubble. I intentionally bogged it down to 800rpm in 2nd H and plodded up the hill to show a mate of mine just what the petrol donk will do when crawling. However - stir them along and they are a bundle of fun as well. I don't think you'll regret it.

Unless you've got big cubic inches or a six cylinder CRD turbo, diesel's start to give me the sh*ts after a while too.

keepingitreal replied:

got a 1hz, aftermarket turbo & 240,000km. Did the r151f (light), gearbox and replaced with H151f (heavy) from a v8 petrol. Got heavy gearbox and transfer (pump for oil ,not drip fed!) as well as turbo flywheel and clutch (much heavier) . all bolted straight in (with different bell housing) and retained old drive shafts with no mods. Gearbox is significantly bigger than old one . Unfortunately has raised engine revs by about 500 @ 100km/h. Diff ratios in newer models are 4.11, mine (live axle) is 4.33. I think i will look at changing mine at later date, hopefully to 3.9/ 3.7's ???, to get cruise speed (95-100km/h) revs down to around 2000rpm. Above all very happy with my conversion, and to be honest cheaper than doing my old box up!!. I can also travel in confidence knowing it is all heavy duty and if need be parts are easily available (ie: clutch). My 2 bobs worth!! keep it real, regards Kirsten (NSW)