LUVTruck.com

Has anyone replaced their standard diff with a taller geared diff? I have 50 series tires on 15" rims and I would like to get better fuel mileage and a little less revs.

_________________
We're all here for a good time, not a long time.
1979 LWB 2WD G180 Weber 32/36 Turboflow Exhaust
1979 LWB 2WD G180 Stock Mikado

It's done all the time, just awap the third member. Your gear options are 3.90, 3.73 & 3.43, pick the one that gives the RPM you want with the tire size you are running. To correct the speedo you have to swap the driven gear on the end of the cable for one with fewer teeth.

_________________
'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.

Do you know where I can get these parts from? Thanks.

_________________
We're all here for a good time, not a long time.
1979 LWB 2WD G180 Weber 32/36 Turboflow Exhaust
1979 LWB 2WD G180 Stock Mikado

Used 3rd members- salvage yard (car-part.com)
Speedo gears- JLEMOND

_________________
'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.

Is Jlemond a Luv Truck member?

_________________
1980 Luv 4x4 with a 5 speed tranny.



"When all else fails, follow the directions".

Not that I know of. He's on the PlanetIsuzoo forum and IsuzuPup.com. I'll PM you his contact info.

Jack

_________________
'83 Isuzu P'up Diesel LS - Original Owner
JoeIsuzu@IsuzuPup.com
IsuzuPup.com

What if you change your tire and rim size. Can speedo be corrected in this case? I have 205/70 R15 on there now.

_________________
1980 Luv 4x4 with a 5 speed tranny.



"When all else fails, follow the directions".

Sorry to jack the thread but, could I get the jlemond info as well?

_________________
1979 Luv 2wd, rebuilt impulse G200, Weber 32/36, Offy intake, Delta cam, Pacesetter header, Flowmaster, 2 1/4 inch pipe, lowered 4 inches, Bed shortened 10 inches, 1997 Tahoe wheels with 225/50R16 Toyo Proxes.

Zane: yes, see how many teeth on your driven gear now (probably 20), calculate how much your odometer is off (say it's reading 10% low). 20 teeth - 10% = 18 teeth. Not exact, but close enough.
Costa: e-mail, also his paypal account address:
jlemond@bellsouth.net

FYI: these gears are not cheap, about $26 plus shipping. When I first changed mine 30+ years ago they were under $5, available at the local Chevy dealer. You may can still find a salvage yard replacement, with stock tires 4.10 gears often had 20 teeth, auto tranny/3.73 gears 17 teeth, 3.42 gears 16 teeth, Trooper 4.56 gears 19 teeth (bigger 15" tires)- it all depended on what size tires came with the truck & the gear ratio. I don't know if they are interchangable between the 4 & 5 sp MSG transmissions & across the different years.

_________________
'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.

PM sent...

Jack

_________________
'83 Isuzu P'up Diesel LS - Original Owner
JoeIsuzu@IsuzuPup.com
IsuzuPup.com

Is the driven gear located on the transmission where the cable attaches? I believe there's a metal tab where the cable attaches on the tranny that will come off.

_________________
1980 Luv 4x4 with a 5 speed tranny.



"When all else fails, follow the directions".

Autos had 4.10 rear gears, but I don't know about the number of teeth because the driven gear MIGHT not have been the same as 5-speeds.

5-speed gassers with 4.10 gears had 20 teeth (6x20).

Also, the 3.73 gears came with 18 teeth (6x18).

Jack

_________________
'83 Isuzu P'up Diesel LS - Original Owner
JoeIsuzu@IsuzuPup.com
IsuzuPup.com

The driven gear is attached to the end of the speedo cable, held into the tranny with a retainer bracket, has different numbers of teeth. The drive gear is internal to the tranny and has 6 teeth.
Jack- a '78 LUV with auto tranny had 3.73 gears & a 17 tooth speedo gear, this gear is what I used to adjust the speedo on my LUV when I went from the 28" tires that came on it to 31's, but this was back in 1979, so obviously the tire sizes, rear gear & speedo gears came in many different combinations throughout the following years.

_________________
'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.

Well ya know, I didn't even think about this being a 1st-gen and even if I had, I would not have known that I didn't know this. Learn something new every day!

Jack

_________________
'83 Isuzu P'up Diesel LS - Original Owner
JoeIsuzu@IsuzuPup.com
IsuzuPup.com