Outer Limits 4x4 Board

G'day,

can someone tell me if it is a direct swap in to put a H150 into a 1hz 100 series? i.e same transfer case, clutch etc?

If i have my facts straight, the 1hz 100 series has an R151 box yeah?

A mate of mine has a 100 series 1hz with an aftermarket turbo, and he tows a camper trailer with it. I told him i don't know how many times before he bought it that the gearbox will shit itself, and lo and behold, it has. I've told him not to replace it with another R151, as it will only break again, and to get an 80 series box put in.

so is the H150 (or H151?) a simple bolt in?

cheers.

yes and no...the shifter is different 80 to 100, so a petrol h151 gearbox has the right shifter...and transfer if you want constant. You then need a diesel 80 bellhousing to bolt on and it becomes a turbo diesel box. OR a h150 from a diesel 80 and get a 100 shifter for it. If you run part time transfer, any transfer from an 80 will work, if it is constant, the shift motor from what you have will fit the 80 transfer, as the plugs are different....the biggest problem you will have is getting the right clutch spline. turbo diesel and petrol have the wrong spline, and the fix is a izuzu clutch plate worth $450....so the best option is later 80 h150 diesel gearbox and a 100 series petrol shifter (or rebend the 80 one)
The box will fit straight in, get tailshafts too as the 80 had larger unis....crossmember aswell just incase...5th gear in a h gearbox is lower than the r gearbox, so the motor will rev more in 5th...but you wont break it
Andrew

Have a HZJ79 with blown R151 gearbox at work and wanted to know if i could replace it with a H15# box from a 75 cruiser?

The owner is pretty hard on the ute.
It is just a straight 1HZ no turbo with 300,000 on the clock or is it easier to go with a rebuilt R151?

Cheers
Matt

The HZJ75 had the H55F gearboxes. I am not sure that the H55F will go into a 79 series easily, the tailshafts would be different lenghts.
Might be easier to use the H150/H151 from a part-time 4WD 80 series.

Frankenyota wrote:Have a HZJ79 with blown R151 gearbox at work and wanted to know if i could replace it with a H15# box from a 75 cruiser?

The owner is pretty hard on the ute.
It is just a straight 1HZ no turbo with 300,000 on the clock or is it easier to go with a rebuilt R151?

Cheers
Matt

use the turbo diesel box out of a hdj79 bolt straight in but a little pricey

excuse my ignorance but whats wrong with these gear boxes ?

twocs wrote:excuse my ignorance but whats wrong with these gear boxes ?

I would ask the same thing given a mate of mine has been towing a 20ft van for years with his without drama yet this one has broke in front of a camper trailer.

The R150 doesn't use a layshaft for 5th gear thus making it stronger. If you pull them apart the R151 has the 5th gear sort of tacked on the side like it was an after thought.
As with anything mechanical it comes down to use/abuse.

What is the box from a HDJ79 a R or H box?

LuxyBoy wrote:The R150 doesn't use a layshaft for 5th gear thus making it stronger. If you pull them apart the R151 has the 5th gear sort of tacked on the side like it was an after thought.
As with anything mechanical it comes down to use/abuse.

So the issue would generate more from towing in 5th gear rather than the box overall???If so that would make some sense as he would be unlikely to be towing in 5th all the time with a 20ft van on compared to someone with a camper would could quite feasibily do so???

fester2au wrote:

LuxyBoy wrote:The R150 doesn't use a layshaft for 5th gear thus making it stronger. If you pull them apart the R151 has the 5th gear sort of tacked on the side like it was an after thought.
As with anything mechanical it comes down to use/abuse.

So the issue would generate more from towing in 5th gear rather than the box overall???If so that would make some sense as he would be unlikely to be towing in 5th all the time with a 20ft van on compared to someone with a camper would could quite feasibily do so???

Exactly right, that is why you shouldn't tow with most vehicles using 5th gear regardless of weight being towed.

well in actual fact he only towed the trailer with it for a few thousand km before it broke. I think what contributed more to it's downfall was the fact that the previous owner put an aftermarket turbo on the 1hz long before my mate bought it.

correct me if i'm wrong, but i thought that the r-series boxes were just weaker in general than h-series - i.e not just the 5th gear.