Mechanics....advise please.

[mtn_extreme]

Here is my situation:


Have a 1971 chevy 3/4 ton 4x4 that has a mildly modded 454ci. engine. Behind that is a 700r4 tranny that links to a np205 transfer case.
Well, lost the tranny a month ago pulling my travel trailer (didn't put it in myself, suspect it to be a stock 700).

Anyway, here is my question. Want to replace the tranny with a rebuilt one and I am not sure who to go with. There seems to be a wide variance in price range and as I am not very familiar with internal parts, I am kind of lost here. My application needs to handle fairly heavy duty, probably in the 500 hp + range.

It has been suggested to me to go with Monster Transmission but I have been leaning towards PATC's Raptor series. There is almost 1000.00 difference between the two though.

Any suggestions or advice on who, where, what, etc. would be a great help and greatly appreciated.

MX

 

[AKSNOWRIDER]

personally I would go to your local gm dealership and buy a remaned factory tranny..they have all the latest upgrades, the best warranty you can get and they last.............problem with a local tranny shop rebuild is the quality...and the aftermarket trannies also dont seem to get all the latest updates and dont seem to last either...I have installed quite a few gm remaned trannies behind some well built motors and never had a problem with any of them...if you are worried about it get a newer 4L80 and an aftermarket install kit for it(includes a custom ecm, wireharness and all parts needed to install)and it will live behind the bigblock.......

 

[hilinerider]

x2 on any 700r4 needs to have ALL the updates to last, or 4l80e


or a turbo 400 that would have come with that year

 

[mtn_extreme]

".............problem with a local tranny shop rebuild is the quality."

The two listed are not local tranny shops, they specialize in high performance transmissions and build to your applications along with all upgraded hi-performance components. I am just not knowlegable enough to know how one compares to the other to justify 1000.00 difference in price.........or difference in price over as you suggest, for one from gm (what is that cost approx).

 

[AKSNOWRIDER]

".............problem with a local tranny shop rebuild is the quality."

The two listed are not local tranny shops, they specialize in high performance transmissions and build to your applications along with all upgraded hi-performance components. I am just not knowlegable enough to know how one compares to the other to justify 1000.00 difference in price.........or difference in price over as you suggest, for one from gm (what is that cost approx).

yes mnt I knew they wernt locals..have never dealt with them...so no idea on their quality...I have bought complete trannies (built heavy duty to full race) from B&m, TCI, and G.E.R. ..none of them held up to what they said they would, all of them fought warranty coverage and in the end I fixed them myself for my customers...started using factory remaned trannies even in some hot cars and never had a problem with them..expense wise the gm trannies were a grand more then our local rebuilders but that was a small price to pay to never have to touch it again...also the gm warranty is good nationwide...and even though they didnt install it..they still R&R when it is warrantied..thats tough to beat on a driver..........

 

[mtn_extreme]

Thanks for the advise, do you have an approximate on cost thru gm or about what you think....the monster is 1500.00 and the raptor is 2500.00

 

[AKSNOWRIDER]

Thanks for the advise, do you have an approximate on cost thru gm or about what you think....the monster is 1500.00 and the raptor is 2500.00

I havent bought a tranny in at least 6 yrs mnt..but I would guess a 700 would set you back 1300 + today...call the dealer and ask...regardless who you buy from..get a written warranty..including what is required for install(such as flushing cooler lines, what exact fluid is ok,what constitutes abuse and such) reason why I had a customers B&M tranny start slipping 2 weeks after install and B+M wouldnt warranty it cause it had a crate big block and the car was sold with a small block new(yet when I ordered it they said motor didnt matter and they knew exactly what crate motor it had) that tranny I fixed myself, was the last B+M anything I ever bought.......(bad deal to me..the motor overpowered the tires so bad there is no way it could have loaded the tranny enough to hurt it.. it had a cut direct clutch piston seal on assembly and they just didnt want to warranty it...)

 

[Xfired]

You need to make sure you have the correct output shaft on the tranny, stock one is to long. From all the research I did for my truck, the 700-r4 and np205 were never mated together from the factory. Advanced Adapters makes an output shaft for the tranny. I did not go that route, had the tranny shop cut the end of the shaft off, no problems in the 5 or 6 years that I have run that combo.

 

[mtn_extreme]

Yes. I don't go directly to the transfer. I have an adapter that has a collar for both shafts. Think this is actually what took out the tranny as the seals went bad and I lost all tranny fluid into the transfer. Though I caught it early enough but apparently not.

 

[hilinerider]

Yes. I don't go directly to the transfer. I have an adapter that has a collar for both shafts. Think this is actually what took out the tranny as the seals went bad and I lost all tranny fluid into the transfer. Though I caught it early enough but apparently not.

sweet lookin setup, my 70 is a 3/4t 4sp with a 350, love the 67 to 72's

 

[mtn_extreme]

anyone else know anything about these companies?

Thanks