LUVTruck.com

Has anyone ran this gear combo before and is the truck just absoluetly gutless? I found a set of gears but I am afraid I will just get crumby highway mileage because the motor will have to work so much harder to turn the gears to maintain speed. What I have is a 78 luv with the stock motor and tranny and it is 2wd plus the basic upgrades like the weber and header. Also running a 275/60/15 for rear tire. Looking at doing a electronic dizzy over the winter to make it more efficient as well. Anyhow.... I dont know exactly what gear is in it right now but I am sure its not the 3.42 gear because it is not a mpg package luv. I believe it has 4.10 from the factory. Any other opinions are appreciated. I am aware of the 5 speed swap possibility but curious about this route. Thank you all,
Jeremy

3.42 rear + 4speed trans + 28' tyres at 50mph = 2052rpm

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1980 4x4 KBD40 ISUZU/Chev Luv
Factory Fitted c190 Diesel Engine, ARB BullBar, Ramsey Winch, Custom Tilt Tray,

indeed. i am pretty sure that ratio would make your highway mileage considerably better by lowering your RPM at highway speed.

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Luvless
1980 Mikado-Sold.

1993 Lexus SC400 my Daily
2004 Yamaha WR250F my new love in life
2016 Toyota Camry my girls ride

Be aware that you're completely altering the powerband of your truck. I have this combo right now and around town it's great. You will quickly find out that on the highway you will be kick it in the guts to build up high speeds and it won't hold them on any kind of an incline. These motors just don't have it in them without some work. It would be a great set of gears if you had a better engine.

It all depends on how flat your roads are and how fast you really need it to go. Florida is perfect for this, which is why I installed 3.42s.

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1976 2x4 LUV: 4-speed, 32/36 Weber, desmogged, 3.42 gears

My '76 LUV and Impulse 5-speed for sale:
viewtopic.php?f=8&t=24576

That's about 20% taller than you're running now and about 24% taller than stock.

I think the truck would be so gutless you'd just end up in 3rd gear all the time.

You could put a little bit taller tires in the back and split the difference.

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You went there in that?!?!

Do any of you all happen to know what my truck has in it from the factory at all?

And thank you all for your replies as well.

It's probably a 4.10. Is your rear end a 10 bolt? I don't think they made 3.42s for 10 bolts. The only 3.42s came in diesel's with 12 bolt rear's as far as I know.

From the 1978 factory service manual- manual trans had 4.10 gears (and a 20 tooth speedo gear), auto trans had 3.73 gears (and a 17 tooth speedo gear). If you start changing tire sizes or gear ratios you have to correct the odometer with the correct driven gear.

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'78 Chevy LUV,1.9,4sp,headers,31's,SAS Dana 30,Dana 20,SOA rear w/Aussie Locker, rough body, bought new 12/4/78.
'87 Trooper,2.3,5sp,headers,31's,ball joint flip & spacer,Aussie Locker rear,Superwinch hubs,brush guard w/5.5K winch,more to come.

Yes my rear end is a ten bolt. Will have to look in further to the 12 bolt situation.

I thought all 12-bolts were disc brake? My 3.42 is from an '84 Pup with drums and I believe it's a 10-bolt.

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1976 2x4 LUV: 4-speed, 32/36 Weber, desmogged, 3.42 gears

My '76 LUV and Impulse 5-speed for sale:
viewtopic.php?f=8&t=24576

Isuzu 10-bolts with 3rd members that will swap into a LUV came with these gear ratios:
3.42- some diesel & '84 MPG Pups
3.73- auto trans LUVs, maybe others
3.90- RWD Impulse
4.10- most manual LUVs, Pups, '87 TD Troopers
4.56- very early LUVs, '84-'87 Troopers
4.77 fronts were made, if they were offered in a rear 10-bolt it would be for RAB system and the third won't fit a LUV axle housing. The ring & pinion gears could be swapped into a LUV carrier, as could the 5.12 from Indonesia and the 5.38 from Iceland- if you can find them.
Anyone disagree or have more info please chime in.

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'78 Chevy LUV,1.9,4sp,headers,31's,SAS Dana 30,Dana 20,SOA rear w/Aussie Locker, rough body, bought new 12/4/78.
'87 Trooper,2.3,5sp,headers,31's,ball joint flip & spacer,Aussie Locker rear,Superwinch hubs,brush guard w/5.5K winch,more to come.

diesels in the states where never sold with a 12 bolt in the rear, only the 10 bolt.

1984 is as far back as the epa mpg ratings go, no data at all listed for older autos
thers one gasser listed with better mpg than the 5sp so its gotta be the 3.42 gears
http://www.fueleconomy.gov/feg/calculatorCompareSideBySidePopUp.jsp?column=1&id=27253


there was a small number of diesels sold in CA state with the 3.42 and the 14.5% O\D its rated mpg is less than the 3.42 with 4sp.

3.42 with 4sp
http://www.fueleconomy.gov/feg/calculatorCompareSideBySidePopUp.jsp?column=1&id=27256
3.42 with 5sp
http://www.fueleconomy.gov/feg/calculatorCompareSideBySidePopUp.jsp?column=1&id=28262

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86trooperT/D 2.2
84 L\B 4x4Diesel LS 2.2
84 S\B 4X4 gas rust bucket 1.9
86 L\B 4X4 gas 5 speed 2.3
the twins, 81 pup and 81 LUV both are diesel 2.2



The Energizer Bunny is trying to keep up, and is starting to gasp for air!!

my 81 gasser has the 3.42 with a 4spd. And I have a 84 mpg diesel / 3.42 with a 5spd from the factory, california model, or I should say I had. Now trooper/t has the cab and soon have the frame.