TH350 To a 700r4 transmission

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Royal Sierra 454

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I just started looking into installing a 700R4 transmission. I call Monster Transmission. They took all of my specs. Upgraded 700 R4 transmission kit and a 3-year unlimited mile warranty. Said this build will be able to beating. Not cheap, but what is now days? Have anyone done this swap and would like to hear your results.
 

NickTransmissions

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I just started looking into installing a 700R4 transmission. I call Monster Transmission. They took all of my specs. Upgraded 700 R4 transmission kit and a 3-year unlimited mile warranty. Said this build will be able to beating. Not cheap, but what is now days? Have anyone done this swap and would like to hear your results.
How much is Monster charging and what are you getting for it? You gave them all of your "specs" - did they give you theirs for their trans?

The swap itself is straightforward. You'll need to move your x member back a bit, cut and rebalance your driveline and make sure to set up and adjust the TV cable correctly.

Depending on your final drive ratio, if it's too tall it will also have to be upgraded.
 

Royal Sierra 454

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All new transmission, All upgrades will be done. Come with the 700R4 to NP205 transfer case adaptor. Cable, fluid and shipping. 5K yikes. Complete Kit. I called Hughs Performance in Phoenix. I was like ordering a la carte for a off a menu. Close to 7k
 

Royal Sierra 454

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Nick Transmission, can you hook me up? Do you feel the 700R4 is an okay way to go? I see an 700R4 and adaptor on CL only $75
 

NickTransmissions

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Nick Transmission, can you hook me up? Do you feel the 700R4 is an okay way to go? I see an 700R4 and adaptor on CL only $75
Let me send you a PM with my contact info and perhaps we can chat...Im in Vegas so not too far from you...
 

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You can rebuild a good core 700R4 with upgrades for less than 5k. You could even do it yourself if you wanted too.
 

GTX63

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For a poor slob on a budget, I had a local old school transmission guy rebuild a 700R4 for me, doing a complete thru and thru, with a new torque converter for $1300.
I'd prefer to take 5-7k and spread it lightly from the front bumper to the back.
 

Bextreme04

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I agree, 5K makes it hard to justify the swap. Talked to Nick, Great guy and he's going to set me up with a nice 700R4 transmission.
That's great. 700R4's can be done right, but they can also be royally screwed up. It's important to get it done by someone that knows what they are doing and is willing to stand by their work. Nick is still new here and hasn't really built a reputation here as far as I know... but I haven't seen any comments from him that didn't seem spot on either. This seems to be a good start for him to either be able to build his reputation on the forum, or not. Please make sure to report back on this post with a follow up either way!

P.S. I'm sure that Nick will tell you the same thing, but the longevity of a 700R4 can be completely destroyed by incorrect installation and adjustment of the TV cable. Make sure it is either being installed by Nick or another reputable shop that properly adjusts the TV cable(preferably using a line pressure gauge) before trying to drive it. I would also recommend putting a nice big trans cooler up front and plumb it in after the radiator cooler. I would recommend a tru-cool 40k or an M7B or H7B.


Also, for anyone else reading this in the future: STAY AWAY FROM MONSTER TRANSMISSIONS!
They have a terrible reputation in almost every forum and group and have an absolutely terrible rating on BBB due to their absolutely horrible business practices and failure to actually deliver what they promise. There are many instances of people buying one that supposedly has been "Built Right" and when they tear it apart it has used stock parts and all kinds of issues. They just aren't worth it. Find a reputable builder or someone local that that has a good reputation and is known to stand behind their work.
 

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My truck has a 700R4 that came from the previous owner. There are pros and cons to everything so please be prepared.
 

NickTransmissions

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That's great. 700R4's can be done right, but they can also be royally screwed up. It's important to get it done by someone that knows what they are doing and is willing to stand by their work. Nick is still new here and hasn't really built a reputation here as far as I know... but I haven't seen any comments from him that didn't seem spot on either. This seems to be a good start for him to either be able to build his reputation on the forum, or not. Please make sure to report back on this post with a follow up either way!

P.S. I'm sure that Nick will tell you the same thing, but the longevity of a 700R4 can be completely destroyed by incorrect installation and adjustment of the TV cable. Make sure it is either being installed by Nick or another reputable shop that properly adjusts the TV cable(preferably using a line pressure gauge) before trying to drive it. I would also recommend putting a nice big trans cooler up front and plumb it in after the radiator cooler. I would recommend a tru-cool 40k or an M7B or H7B.


Also, for anyone else reading this in the future: STAY AWAY FROM MONSTER TRANSMISSIONS!
They have a terrible reputation in almost every forum and group and have an absolutely terrible rating on BBB due to their absolutely horrible business practices and failure to actually deliver what they promise. There are many instances of people buying one that supposedly has been "Built Right" and when they tear it apart it has used stock parts and all kinds of issues. They just aren't worth it. Find a reputable builder or someone local that that has a good reputation and is known to stand behind their work.
No one is perfect however I do stand by my work 100%...Please don't correlate my tenure here (or any other forum or the age of my YT channel) with my time on transmissions, esp the 700R4/4L60E. I taught myself how to build them over 10 years ago because I got ripped off by a transmission shop when I was a teenager (20 years ago) and was forced to sell a car (86 Caddy Fleetwood Brougham) that I loved because I was a broke college kid 1,850 miles from home who couldn't afford to pay twice for the a job that should have been done right the first time. Told myself that would never happen again...

So fast forward about 9 years after the fact and the 700R4 in my R10 Long Bed started to slip. By that time, I had already rebuilt several SBCs, BBCs, Ford 460s along with few Mopar 440s as well as done everything from brakes to rear ends on cars/trucks. So the next logical step was the transmission. Went to the junkyard, purchased a 700R4 core after researching what years would work best, etc. and spent the next two weeks tearing it down bit by bit, taking copious notes and pictures then reassembling it exactly how it was, with new clutches, seals, gaskets, filter, etc. I also watched every video available and purchased two different rebuild manuals so had my bases covered. Swapped it in, set up and adjusted the TV cable and drove it, and sure enough it worked!

Discovered I really liked it so I rebuilt the original 700 within a couple more weeks and then a couple colleagues' 4L60Es and the rest is history.

I know that platform very well and yes, it's true you can mess things up bad if you don't know what you're doing w/the transmission but that applies to most any of them (except for the 200-4R as those can be very, very tricky regardless of diligence level and take sometimes 2x longer to physically rebuild). The TV cable is really the biggest risk point in the whole process for shops or DYI installers, as you mention...If it's not set up correctly (geometry) and not adjusted correctly (tension) then the transmission won't last more than a few miles. I provide a full set of instructions and guidance to customers for all TV-based transmissions I build so I know they have the information they need to get started (and am available for questions whenever need be).

The set up process, in brief, is this: start by hooking up the cable w/full tension while gas pedal is pressed to the floor such that the cable is tight. Then hook up a trans pressure gauge and validate your initial adjustment via pressure testing. Make micro adjustments as needed. Pair that process with Sonnax TV sleeve / plunger and TV valve in the valve body (which @Royal Sierra 454 will be getting, among other upgrades) and you'll set up that transmission for success.

Pressures at idle should be 65-80 PSI or so in P, N, D,D3 | 95-120 in Reverse | 160-180 in manual 2nd and Low
Pressures at stall should be 140-175 or so in D,D3 and roughly the same in Manual 2 or Low as they are at Idle (you get full TV pressure at idle in Man2 and Man Low)

If the 5/16" TV exhaust check ball is reinstalled and stall pressures are present at idle, that indicates the TV cable has not been adjusted with the correct tension and the TV exhaust check ball has seated, maxing TV line pressure. GM introduced that 5/16" check ball in the mid-80s to address failures due to TV cable snapping or becoming unhooked, etc.

X2 (or X100) on Monster.
 

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