Which auto tranny is the best?

[adamforsythe]

Hello,
What tranny would be best for my truck? mudding, street, light off roading (I.E. Hunting, camping, ect). The power plant will be a 350 4 bolt pushing around 450HP with 3.73 and a Np205 maby a doubler.
Thanks
Adam

 

[Inu-Hanyou1776]

4L60 and 700-R4 are the same transmission. 4L60E's an electronic version of the 4L60. 4L80E's a slightly modernized, electronic-overdrive version of the TH400.

Based on your engine's power levels, I'd go with either a TH400 or a 4L80E if you NEED an overdrive along with the strength.

 

[trailblazr81]

You can easilly get a 700R4 to handle the power. And you'll have an OD thats not all electronic. If you dont care about an OD go TH-350 or 400. An Alison would rock!! What size tire? I would only do 3.73 if I wasnt going much over 33" I run 35's with 450 HP 383 and 4.10's. My last Blazer was 383 700R4 and 4.56's and I think that was great for 35's. After 37's I would go to 4.88's

 

[down4thakrown]

dont mean to high jack.....but does the 4L80E tranny have the same spline count and bolt pattern as th400???

 

[Inu-Hanyou1776]

dont mean to high jack.....but does the 4L80E tranny have the same spline count and bolt pattern as th400???

You talking T-case bolt-pattern?

 

[down4thakrown]

yea, but did the seach and found this...........
http://coloradok5.com/forums/showthread.php?t=43382&highlight=4L80E+swap

 

[resurrected_jimmy]

I was going to be a smart ass and say a power-glide with a 3500 stall but from what your usage sounds like if you want overdrive go with a 4L80E or if you only need a 3 speed go with a TH-350 (you can beat them like a dead horse and they don't complain)

 

[AussieK5]

Just out of interests sake if your considering the dollars involved for the higher end OD trannies. .......I costed out my yearly mileage non-OD vs OD.

Assuming I would spend 40% (probably much less) of my time in OD over the course of a years driving, I would save the grand total of $240.

Or to put it in real terms I would see a 14% saving on fuel cost per annum ($2500 down to $2140).

A cheap rebuild on an existing 350/400 is looking real good in financial terms.

Jason

Note: Engine wear is not considered and may be, for you, like me, irrelevant.

 

[wasted wages]

700r4 = sucks
T-400 = rocks

 

[beastofablaze]

You can easilly get a 700R4 to handle the power. And you'll have an OD thats not all electronic. If you dont care about an OD go TH-350 or 400. An Alison would rock!! What size tire? I would only do 3.73 if I wasnt going much over 33" I run 35's with 450 HP 383 and 4.10's. My last Blazer was 383 700R4 and 4.56's and I think that was great for 35's. After 37's I would go to 4.88's

Why do you say th350? A th350 is basically every bit as strong/weak as a 700r4 but without OD.

The 700r4 will handle the power with some extra $$$ and parts like the corvette stuff and stouter clutch packs but you can never go too beefy with a tranny.

th400 or 4l80E all the way.

 

[micah]

I love how so many have voted for the TH400... its got quite the cult following, even though in this situation it is obviously not the right choice. light wheeling and street driving? common guys...

my opinion is that the 700r4 is your best bet... if you can spare the coin (quite a few of them...), then 4l80e

 

[Jimmy4matt]

I've had bad experiences with the 700r4, good with the th350, and good with the Allison 1000. The Allison had a hefty OD run, short gears. I'd go 4.88 with 35's, 5.13 with 37"+. My Jimmy is comfortable on the highway with th350, 4.10, 35" The Allison only felt good in Tow/Haul mode otherwise it felt like it was robbing about a hundred horses. Good luck if you go Allison. Electronic controlled and all.

 

[muddybuddy]

ive got 5.13s currently with 35's with a 700r4. cant say how it drives, its still in the process of being put back together. ill report back within the week

 

[mtn. burb]

You can build most tranny's to be bombproof, but I prefer the one that was built at GM to be bombproof. But an OD in the TH400 would be nice ocassionally.

 

[jekbrown]

I love how so many have voted for the TH400... its got quite the cult following, even though in this situation it is obviously not the right choice. light wheeling and street driving? common guys...

my opinion is that the 700r4 is your best bet... if you can spare the coin (quite a few of them...), then 4l80e

assuming gearing is well chosen for the given tire height, there is no reason at all that the th400 can't be used on a street/light wheelin rig. They are hella stout and rebuilding them is dirt cheap compared to a 700R4.

j

 

[89GMCSuburban]

I got my 700 rebuilt for $300.