RB30-RD28 T gearbox compatability.

[mudnut]

After reading up on the RB30 in the article that is posted in the helpful hints thread, it was mean't to be a glorified shopping trolley. It is a shame they had that mindset as a low first gear would have made the RB just as good as the TB.

[Patrol'n]

Yep, that is disappointing. The RB30 is a good engine and runs so smoothly, with smooth gear changes too.

It might feel a bit strange on the road with a lower first gear, but it would help for off road for sure, sometimes I still have to ride the clutch a bit on rocks in 1st low or risk stalling...

[mudnut]

The other thing is hill descent. If you aren't on the brakes the engine runs away, which is a bit dangerous.

[Patrol'n]

The other thing is hill descent. If you aren't on the brakes the engine runs away, which is a bit dangerous.

That's so true, I do find that the engine braking a tiny bit more effective once my revs hit about 3000rpm, and then there is some engine braking although nothing like a diesel engine. I also find if I turn on my air conditioning, I get a bit more engine braking effect since the engine isn't quite as willing to rev with the aircon on. I must admit that I am a little (ok VERY) cautious about muddy descents where brakes are not a great idea.

I would consider reduction gears in the transfer case except that with the limited power of the RB30, I find I need to use low range quite often in soft sand (there's a lot of sand over here in WA), and then I wouldn't go anywhere at any kind of acceptable speed. Although I have been trying to resist modding the engine, I'm still thinking turbo conversion and reduction gears, guess I gotta start saving. Probably cheaper to buy a different vehicle, but I do love my truck...

[mudnut]

The best mods I have made are taking the heater grid from under the carby, blocking the stove pipe diaphragm (in the warmer months, for long trips and water crossings) and fitting headers. The engine is still a bit asthmatic so I am toying with the idea of enlarging the neck of the filter housing. All this has made the engine rev a lot easier and has not been too expensive. I am hoping the RD gearbox has a lower first cog, so if that is available I would fit that to the gearbox while it is apart.

It seems that no one has the answers we seek...

[Patrol'n]

Yep that is what it seems. I have the basic things covered as you have, and I have been told that fuel injection improves it too, but also means peak torque is achieved higher in the rev range, which doesn't sound like a great idea... if you do enlarge the neck of the filter housing and it makes an improvement then I'd love to know what you did so I can give it a shot too.

[mudnut]

There's two ways I think it could be done. Split the neck 20mm off to the side of the Pre-heat flap and weld in a strip top and bottom, or add a hose from the plastic pipe to the side of the filter housing.

[mudnut]

Could someone with an RD28t please post up the transmission number on the ID plate?

[UWN717]

still have gearbox mate wats ur location?????

[sooty_10]

Could someone with an RD28t please post up the transmission number on the ID plate?

I'll try to remember and check the one I have in the shed.

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