Builds Toyota '96 HDJ80 - Cummins 6BT conversion (2 Viewers)

[MauricioR]

The inevitable happened!!! After quite some mods to the engine (around 350HP and around 1000nm later) the 5th gear failed:

Both Counter Shaft and 5th gear shattered.
I had a word with an expert about this... He told me that the H151f is very strong but not strong enough to handle the power the 6BT is delivering, even at this power numbers the original gearbox (NV4500) can fail as well.
By analyzing 1st, 2nd, 3rt and 4th all gears, synchros and everything else is fine, except for 3rd gear synchro it had some wear but nothing serious.
I was told that this was like turboing a 1HZ with a R151, usually after a while the 5th gear fails due to the torque.

Additional to my problem, my transmission had an low oil problem (totally my fault) 2.4 liters were found on the transmission, manual indicates it should contain 2.7 liters.

Conclusion... The Transmission is being rebuilt, both Counter Shaft and 5th gear is being replaced, few other parts are being replaced as maintenance such as the other synchros and some other things.

I was told I can't force the 5th gear, I should use 5th on plain terrain and be gentle with the gas pedal if not the issue will re-occur.



Let's see what happens! Oh! And I broke my 5th gear on a hill climb pull I did at around 100KPH with 37inch tyres .

 

[SegFault]

Ouch! How are you liking the 6BT beyond that what looks like it’s appetite for transmissions lol

 

[MauricioR]

Ouch! How are you liking the 6BT beyond that what looks like it’s appetite for transmissions lol

Well I love it... Tons of power everywhere on the RPM range.
If its keep under 2000 RPM diesel consumption is good (7-9 Kilometer per liter - an Average of 8).

I love how diesel feels and the power of it. Some people prefer petrol and go V8 on this model which is cheaper and you can get equal power numbers but for each person their taste!

I am missing the electrical part of the car, but as soon as I get the Spedometer and RPM meter installed I will make a video for you guys to see

 

[MauricioR]

Engine is a monster on all aspects... I am running 39.5inch Tires with 4.11 gears and pulls like nothing...
I made few mods to the engine such as bigger injectors, bigger delivery valves, 4000RPM limiter, few pump mods, timing...

I can certainly say that if the engine is kept stock with a decent pump timing, 4K RPM mod, the engine will feel just great.
Diesel Pump timing is what makes this engine rattle and make it feel like a big old truck

After rebuilding the gearbox I wanted to take some technical courses about oil... Now I run the following:

*Front and rear differentials: Amsoil 75W110 Severe Gear full synthetic oil.
*Gearbox and Transfer case: Redline GL4 full synthetic MT-90.
*Engine: Shell Rotella T6 15w40 full synthetic.

Now my main issue now is... The OEM clutch cannot handle the power of the engine so is slipping on 3rd gear full gas.
Next upgrade is going to be a SPEC clutch able to handle ~900ft/lbs of torque. Let's see what breaks next

 

[MauricioR]

Well, the journey continues... I believe I will do another thread for the continuation of this project...

These are 42 inch tires.

Because of reasons .. I decided to swap the body of the car... For that I bought a HZJ79:

We will see how it goes...

 

[davegonz]

Check it out @Mr Cimarron .

 

[Mr Cimarron]

Nice!

 

[mjosoba]

Man, I just came back and read page 4 of this thread. What a whirlwind! I can’t wait to see more.

 

[Dirty Koala]

hows the body swap coming along?

 

[MauricioR]

Hi Guys. Sorry for the long time with no updates... I had a daughter and I had to prioritize things up...
The project of converting to the 75 series didn't start, I actually sold it a bit later after I got it. In early 2022 my rear axle broke apart, the ring and pinion completely exploded, I was running ~350hp according to my weight and 1/4 mile time. Initially I thought on rebuilding it but I sold both front and rear diffs and added a front passenger side Dana 60 and rear GM14 bolt.

I drove for another year with no issues but my clutch was way too burned, it was my 2nd clutch in 3 years, didn't want to buy a new one again... So I got a 47RE transmission from a junkyard and a NP205 and started saving money.

My dream for this project was to always get weight off of it, since I didn't like it how it behave on trails (too much weight), that was the main reason of why I wanted to swapped the body.
I stopped the car last year and took it apart completely. Motor, diffs, transmission and transfer (47re & np205). I cut the car in half and made it an "Extra Cabin" version:

This photo is from last week.
Diffs were rebuilt, suspension and everything is the exact same thing as before.
The motor was rebuilt completely with few upgrades on it to hold some power, the transmission is at 80% (Waiting for the billet input shaft to arrive), the transfer is done at this point...
It has been quite a journey with this car... To be honest, would have been a lot easier to just get an ugly 80 series and a Dodge Ram and just swapped everything out but well... I did it the hard way.

Is still a long way ahead, I took most of the electric harness out, so I need to build it from zero. I need to make transmission and transfer mounts and cut to size the drive shafts among several other things...

 

[MauricioR]

Oh! If you wonder where I took the idea of cutting it in half... I follow these guys called "Winch Trucks Australia"... Man I really like these rigs.
Winch Trucks Australia - https://www.facebook.com/winchtrucksaustralia
Hopefully mine will look alike some of those.

 

[MauricioR]

 

[MauricioR]

 

[MauricioR]

 

[MauricioR]

 

[MauricioR]

 

[MauricioR]

 

[bsweaty]

the world needs more of this.