R151F behind a turbo'd 1HZ or 1HDT (2 Viewers)

[crushers]

no, the R151 doesn't hold up "fine". the R151, R141 are a weak tranny.
example:
H55 has never let me down or broke no matter how abusive i have been in the bush.
R151 started making noise at 80,000 km behind a PZ turbo.
a BRAND NEW out of the box R141 began making noise at 3000+/- km behind the same engine with 36" tractor tires on the first abusive trail run.
5000 +/- later and it pops out of gear, grinds occasionally going into 3rd and is very noisy.
they are s*** trannies but for daily light duty use, they are a nice tranny to drive. the few H151 is a crappy shift, piss poor gear selection.
just my experience in answer to Lee's question.

 

[TheBigBoy]

Yes, the R151 DOES hold up just fine. They are the factory box for 75/79/80/105 1HZ's. Thousands of them turbo their 1HZ or do engine conversions without changing the gearbox. Turbo'd a 75 series 15 years ago and its still going strong. We turbo heaps of them and run 200+ hp through them and no issues. The H151 the next step up. I have no idea what your talking about with crappy shift/piss poor selection. They feel great to me and millions of others that have a factory turbo diesel cruiser.

 

[Hulsty]

TBB your confused, got your gearboxes mixed up. R151 is only in Hilux's, Bundys, 79 series 1HZ N/a, 105 series 1HZ N/A, various 1PZ's its a dog of a box, piss weak, designed for lighter loads and smooth shifting, related to the R series boxes in various Toyota 2wds. 75 series has the H55F, ALL 80 series use a H150 or H151, much stronger. ALL factory TD cruiser use the heavier H151, physically and much larger stronger box.

 

[crushers]

hey, if he like those s*** boxes, more power to him.
<shrug>
maybe he swapped out the H55 that came in his 75 series for a R151?
or maybe he didn't know his 75 has a H55 from the factory
???

 

[AussieHJCruza]

R151 is dicey behind a turbo 1HZ imho. My cousin broke his R151 in his turbo and intercooled HZJ105 dual cab (had 160kw at all 4 on the dyno) in a boggy spot on his farm. Sheared off reverse gear trying to rock it out. There's a reason the 1FZ-FE, 1HD-T etc came with the H151...

 

[hzj79lee]

no, the R151 doesn't hold up "fine". the R151, R141 are a weak tranny.
example:
H55 has never let me down or broke no matter how abusive i have been in the bush.
R151 started making noise at 80,000 km behind a PZ turbo.
a BRAND NEW out of the box R141 began making noise at 3000+/- km behind the same engine with 36" tractor tires on the first abusive trail run.
5000 +/- later and it pops out of gear, grinds occasionally going into 3rd and is very noisy.
they are **** trannies but for daily light duty use, they are a nice tranny to drive. the few H151 is a crappy shift, piss poor gear selection.
just my experience in answer to Lee's question.

Hi Crushers, is the noise come from the transfer? or which part of the gearbox have some weakness? any parts that we can swap into it to make it stronger except for swapping whole gearbox?

 

[hzj79lee]

Yes, the R151 DOES hold up just fine. They are the factory box for 75/79/80/105 1HZ's. Thousands of them turbo their 1HZ or do engine conversions without changing the gearbox. Turbo'd a 75 series 15 years ago and its still going strong. We turbo heaps of them and run 200+ hp through them and no issues. The H151 the next step up. I have no idea what your talking about with crappy shift/piss poor selection. They feel great to me and millions of others that have a factory turbo diesel cruiser.

factory hzj75 comes with h55f, while fzj75 and hzj80 comes with h150f.

I think different people has different opinion in shift selection since both gearbox has different gear ratio, it depends on our tire size, diff ratio, cruising speed range and our needs.

 

[crushers]

the PZJ75 comes with the R series tranny, road use had the R151, mine use had the R141. just to be clear.
the 80/81 diesel comes with the H15* tranny.
talk to your local mine repair places, they HATE the R series in the mine trucks in the HZJ79 series. they also loved the H55 in comparison to the R.
ENS Toyota is Saskabush have become very adept at rebuilding the R series, reverse is the weakest gear and then something to do with 1st as well.
in my case, i was hoping it was the t/case so i swapped it out. the truth showed its ugly face when the noise went away and the grinding started. sadly, i really enjoyed the R141 enough to take out the mine tranny and purchase new just to be let down quickly. I was warned not to install another R series.
happily, i do know now i can install a H55 behind a PZ engine into a 70 series.

desperation can lead to revelation.

 

[TheBigBoy]

Yeah, I don't know what I was thinking. Appollogies to all.

Its the H55 and H150.

 

[hzj79lee]

Do you know any of those gearboxs transfer case can be swapped with each other? Thank you.

 

[crushers]

i know little about the H15* other than the few i drove i disliked. Others that drove the HDJ81 manual felt the same impression after driving the H55 in the 40 and 60 series
the t/case from the R series and the H55 series are interchangeable. the H4* t/case is not.
this help at all?

 

[Hulsty]

What ratios are in a r series case

 

[crushers]

1.96 t.case, same for the HZ and PZ

 

[Hulsty]

Thanks, was hoping for 2.44 as a easy source. Will stick with my 2.29's

 

[hzj79lee]

I see. Thank you.

 

[SaturnAscends]

I know this is an old thread, but I find it fascinating that the R boxes don't hold up very well behind the 1HZ. I guess it goes to show how big of a factor vehicle weight is. You hardly ever hear about issues with the R150f in a Tacoma or 4runner. The closely related R154f has been reported to tolerate up to 700 hp at the wheels. Given this, it seems hard to contemplate that they'd be so fragile behind a comparatively anemic 1HZ, turbo or not.

 

[Gun Runner 5]

I know this is an old thread, but I find it fascinating that the R boxes don't hold up very well behind the 1HZ. I guess it goes to show how big of a factor vehicle weight is. You hardly ever hear about issues with the R150f in a Tacoma or 4runner. The closely related R154f has been reported to tolerate up to 700 hp at the wheels. Given this, it seems hard to contemplate that they'd be so fragile behind a comparatively anemic 1HZ, turbo or not.

I know if it’s on the internet “it’s true“ but I’ve been running a R151F behind a turbo-charged 1HZ without issue for quite a while.

 

[RHINO]

And I ran one behind an Isuzu 4BD1T with no fuss.

 

[dare]

I know this is an old thread, but I find it fascinating that the R boxes don't hold up very well behind the 1HZ. I guess it goes to show how big of a factor vehicle weight is. You hardly ever hear about issues with the R150f in a Tacoma or 4runner. The closely related R154f has been reported to tolerate up to 700 hp at the wheels. Given this, it seems hard to contemplate that they'd be so fragile behind a comparatively anemic 1HZ, turbo or not.

The bigger problem with the R151 in HZJ79s is the splined adapter between the gearbox and transfer as opposed to the strength of the gearbox itself. The splines fret, strip out and without warning you're left stranded with a box full of neutrals and a rather expensive repair bill. In early vehicles this was a big problem but I'd say most of those have been rebuilt by now. You can buy improved design mainshafts/transfer inputs but they're still a 2 piece shaft.

IME the HZJ79 R151 is quite strong but the fatigue life in that application is poor. Certainly, the R series gearboxes are proven to take a lot of power. It's a similar situation to the R380s in Land Rovers, people put plenty of power through them just fine but the average joe is needing to rebuild them earlier than you'd expect to in a heavy duty vehicle.

I think it's blown out of proportion a bit, people expect Landcruisers to be supremely reliable and it is a really s***ty failure to have so it's understandable that plenty of noise gets made about it. Still, if I was looking at buying a HZJ79 I'd either be looking for one that's been recently rebuilt with the improved parts or be swapping in a H15x.

 

[Gun Runner 5]

@dare …. “I think it's blown out of proportion a bit”
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