REALLY dumb question

[BubbaJ]

I know this is a dumb question but bear with me cuz i'm having brain fade. My question is Can you put V6 gears into a 4cylinder front end without major modification?? dumb yes...but i need to know because i'm ordering 4:88's on wednesday.....Gracias:beer:

[MaverickToy81]

Not a dumb question...but I actually dont know the whole answer. I have heard of swapping in V6 third members in the rear, I dont THINK you have to do any modification to make it work, but I could be wrong. I really have no clue about putting a V6 third in the front. Hell, I havent even heard of it being done, but I am still pretty new to it all in the grand scheme of things.

Hope this helps a bit.

Ian

[My85'Runner]

I would really love to know the answer to that question as well. Seems your question is not as dumb as you thought, many want to know the same thing, so kudos to you for being the one to ask:beer: .

[AZWILDYOAT]

If you are talking about putting a V6 third w/ gears into a front 4 cyl. housing, then yes you can w/o any modification.

[My85'Runner]

Okaay if you can just plop a V6 third into the axels then why doesn't everyone run the V6 gears, aren't they better than the 4cyl ones? Also aren't V6 housings high pinion too? Please set me straight if I'm off in some way, to me it just seems too easy and strange that everyone isn't running them.:Help:

[AZWILDYOAT]

Most people don't run them cuz they cost way more for the v6 3rds than 4 cyl. The gears usually run more along with the install kits. The only hi-pinions are the newer Landcruisers. Some people don't think the V6 3rds are any stronger, but the V6 have a larger pinion and bearing along with a housing that is braced more to prevent flexing.

[AverysDad]

actually ive seen that the 4cyl pinion bearing is larger than the 6cyl........

the 6cyl pinion bearing is smaller to accomodate for the larger pinion gear. i dont know if this will affect the strength all that much but i do know that the 6cyl 3rd member case is more beefy and has more ribs on the case than the 4cyl.

[suv]

Here's some good info from the Pirate FAQ:

There are actually two types of R&P, let's call them "LPH" (Long Pinion Head) and "SPH" (Short Pinion Head).

- '79-'85 rigs have SPH gears and a "thick" inner pinion bearing designed for the 4cyl housing. All aftermarket "4cyl" R&P and inner pinion bearings are identical to these factory parts, that way the same part numbers will fit all '79-'95 four-cylinder rigs.

- '86-'95 four-cylinder and V6 rigs ALL come with LPH gears. However, to use LPH gears in a four-cylinder housing you MUST use the "thin" '86-'95 factory Toyota four-cylinder inner pinion bearing. If you use a "thick" aftermarket bearing (or a factory '79-'85 bearing) the pinion will be too deep into the mesh and won't work.

- SPH gears will fit V6 housings if you add a lot of inner pinion bearing shims. Precision Gear avoids having to use so many shims by offering an aftermarket LPH gearset for V6 housings.

- '88-'95 V6 housings must obviously use V6 inner pinion bearings, so there's no confusion here.

- Carrier bearings aren't an issue here either, just R&P. You need 4cyl carrier bearings for 4cyl housings and V6 carrier bearings for V6 housings regardless of year.


So, if you have a 4 cyl carrier, a V6 ring gear won't fit because it's too thick. But, only Precision and US Gear make the thicker V6 gears, other brands use shims to space the gear out - so other brands would work with the right pinion bearing.

The reason V6 gears are stronger is due to the 3rd member casting. It allows less pinion deflection because it's more rigid. Less deflection = more contact which means less breakage.

[AZWILDYOAT]

Yukon also makes the V6.

[suv]

Originally posted by AZWILDYOAT
Yukon also makes the V6.

You're right...sort of. Yukon doesn't make gears, they just sell other brands under their own label. The V6 gears they sell are US Gear. I just had some installed in my e-locker rear :D

[oregon85wheeler]

Originally posted by BubbaJ
I know this is a dumb question but bear with me cuz i'm having brain fade. My question is Can you put V6 gears into a 4cylinder front end without major modification?? dumb yes...but i need to know because i'm ordering 4:88's on wednesday.....Gracias:beer:
I would go with 5.29s. Too low is way better than too high, in most cases.

[bonejoe18]

Originally posted by suv
You're right...sort of. Yukon doesn't make gears, they just sell other brands under their own label. The V6 gears they sell are US Gear. I just had some installed in my e-locker rear :D


Your right.....sort of. Yukon does make their own gears and they also sell other peoples gears in their boxes.

[Runner-Man]

I noticed that you have a 90 model truck. If you have NOT done an SAS, then this is applicable:

If you still have IFS then you can NOT put V-6 gears from a rear third into the front. The front diff is 7.5" and the rear is 8". All IFS gears for the front (7.5" IFS) should interchange with another front (7.5" IFS), except possibly for stock 4.88 gears. Aftermarket 4.88 gears should fit.

If you have done an SAS, then the full third member from a V-6 (front or rear) should fit. However, I think the gears are different thickness due to differences in carrier between 4 cyl. and 6 cyl. And not all V-6 thirds are Hi-Pinion, but I think that all Hi-Pinion thirds are V-6.

Anyone else out there, please feel free to correct any misinformation in this post, as I am not a gear guru!