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HOW MUCH TORQUE CAN A LT230 HANDLE?


66gaza

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How much torque can a LT230 handle? I did ask this Q on pirate but didn't get any definite answers. Is the weak part the two piece cross shaft?,

how much stronger is the single piece cross shaft? I know LT230's are strong but how strong? BTW the LT230 will be a

1.003:1. I have seen the post about having the shaft cross drilled but will the pto oil feed plate do just as good a job? TIA for any replies.

Gaza

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I would have thought 630 lb ft would be a conservative estimate in light of the fact that the larger v8's develop well over 200 ft lb of torque and have a low gear ratio of 3.7 :1 ish That is well over 740 lb ft. I know people that run 6.5 litre GM deisels and Nv 4500 transmissions in front of them without bother. A properly set up centre diff should be adequate as it uses the same gears as LandRovers optional limited slip rear diff of the late 1960's but is subject to less gear multiplication. The problem is that LandRover never machined and set up the centre diffs correctly at the factory. Only a remachined and blueprinted centre differential, ala Jack McNamara Differentials is capable of its full designed torque capacity.

Bill.

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eliot at www.mez.co.uk runs a twin turbo, twin intercooled, chevy 350 through a bog standard LT230 and has done for years. Considering he blows uprated 4l60e yanks overdrives boxes with ease it suggest that the transfer box is a good un

as you can pick up 1:1 boxes for a tenner most of the time then i wouldn't worry about breakages! just replace them if they ever go pop- although please don't buy too many of them as it will destroy my source of parts.

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Really?

Never heard that one before Bill, can you expand the topic a little please (just to satisfy my own curiosity!).

In the late 1960's LandRover offered as an optional extra a 4 pinion limited slip for Rover type diffs based on the Salisbury Powr Lock design as used in Jaguar Dana 44's. For one reason or another (possibly due to increased halfshaft failures) the option was discontinued after a year or 2. The componentry however was then used in the centre diffs of the LT95 transmission of the first thousand or so RangeRovers, until LandRover decided a limited slip wasn't necessary, so they modified the carrier, deleted the clutch plates and ended up with the normal ''open'' diff we have today. The only difference in the centre diff gears of the LT95 and the Lt230 is the splines of the side gears that power the front and rear output shafts.

Even in the series LandRovers with a 2 1/4 litre engine developing 124 ft lbs of torque driving through a 40:1 overall gear ratio in low one the limited slip rear diff could theoretically be subject to almost 5000lb ft of torque, whereas in centre diff application with an engine that developes 200 ft lbs of torque (300TDI) driving through a 13:1 gear ratio in low one,the multiplied torque the centre diff would be subjected to would be considerably less at 2600lb ft, although whether the cyclic shock loadings when front and rear wheels are scrabbling for traction would increase these figures more for the transfercase than for the rear diff, I don't know.

Bill.

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In the late 1960's LandRover offered as an optional extra a 4 pinion limited slip for Rover type diffs based on the Salisbury Powr Lock design as used in Jaguar Dana 44's. For one reason or another (possibly due to increased halfshaft failures) the option was discontinued after a year or 2. The componentry however was then used in the centre diffs of the LT95 transmission of the first thousand or so RangeRovers, until LandRover decided a limited slip wasn't necessary, so they modified the carrier, deleted the clutch plates and ended up with the normal ''open'' diff we have today. The only difference in the centre diff gears of the LT95 and the Lt230 is the splines of the side gears that power the front and rear output shafts.

Even in the series LandRovers with a 2 1/4 litre engine developing 124 ft lbs of torque driving through a 40:1 overall gear ratio in low one the limited slip rear diff could theoretically be subject to almost 5000lb ft of torque, whereas in centre diff application with an engine that developes 200 ft lbs of torque (300TDI) driving through a 13:1 gear ratio in low one,the multiplied torque the centre diff would be subjected to would be considerably less at 2600lb ft, although whether the cyclic shock loadings when front and rear wheels are scrabbling for traction would increase these figures more for the transfercase than for the rear diff, I don't know.

Bill.

Very interesting, thanks Bill.

The componentry however was then used in the centre diffs of the LT95 transmission of the first thousand or so RangeRovers

I did know that, didnt know where the components came from though.

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if they were fitted to an auto (range rover?) will the R380 bolt onto it?

if not i guess the insides would fit into a standard LT230 casing?

are there more options for txb ratio?

ive heard of one around 1.4 that i think is fitted to discoveries?

cheers

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Fridgefreezer do you mean the LT230 1.003:1 are better made? if so can you explain.

Having had a later LT230 and an early one next to each other it's clear the later ones were mass produced and engineered down to a price, not that they're bad, just that the early one (1.003:1) had a few nicer made bits - like a big intermediate shaft with needle roller bearings and oilways, and IIRC more scope for oil to get into the centre diff too.

I have no tech to back up this opinion, so I could be talking utter rubbish :rolleyes:

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Having had a later LT230 and an early one next to each other it's clear the later ones were mass produced and engineered down to a price, not that they're bad, just that the early one (1.003:1) had a few nicer made bits - like a big intermediate shaft with needle roller bearings and oilways, and IIRC more scope for oil to get into the centre diff too.

I have no tech to back up this opinion, so I could be talking utter rubbish :rolleyes:

Every one of the early needle roller bearing 230 t/cases I have worked on have been in remarkably good condition considering their age and mileage covered,so I tend to agree with you in that I am not certain the later tapered roller bearing intermediate gears were a positive development, particularly in light of the fact that most of the ones I have seen with broken gear teeth had very slack/loose taper roller bearings.

Don't Ashcrofts make a 1.003 gearset incorporating the later wider input and intermediate gear design?

Bill.

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  • 8 years later...

Sorry to resurrect an old thread but if anyone knows the answer it is on here.

Does anyone know how an LT230 will fair if bolted into a ~6 tonne truck and running permanent four wheel drive? I hear they are strong but how strong?

I'm thinking here about my Gaz-66 to raise my gearing. The Gaz V8 is pretty gutless in it's power output (~200lb-ft) but 6 tonnes of back torque inertia is a hefty load to throw back through. Can anyone point to any similar application?

I'd have to run it turned upside down so lubrication will need to be carefully thought out

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