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White Phoenix

Building for Rubicon
Ok next detail.
I will keep it auto and put the 4l80e, so should I do the reverse manual valve body?
I always wanted to do this but not sure how it is with daily driver.
I know it will be better off road, more control.
Anything else I should consider?
I am starting to lean towards a full rebuild but not by me, I will have shift management inc do it they are local here and I had very good success with them, and they have a nationwide warranty 18 months 18k miles.
That way I don't waste time and concentrate on other parts of the build.
 
Ok next detail.
I will keep it auto and put the 4l80e, so should I do the reverse manual valve body?
I always wanted to do this but not sure how it is with daily driver.
I know it will be better off road, more control.
Anything else I should consider?
I am starting to lean towards a full rebuild but not by me, I will have shift management inc do it they are local here and I had very good success with them, and they have a nationwide warranty 18 months 18k miles.
That way I don't waste time and concentrate on other parts of the build.
Anyone have an opinion on the reverse manual valve body for the 4l80e.
If my main use will be adventures on and off road, overlanding basically.
Is that a good setup for it or am I better off keeping it stock?
 
Okay let me clarify first. I have never run one. Reverse valve bodies are usually full manual. I talked to someone about this once. I have been trying to remember who. but they said that it wasn't too bad daily driving. So the biggest reasons I see for going reverse valve body is to make it so you don't need a computer. Or to make it R and 1st right next to each other so you can hit reverse on a steep climb.

Other than that I don't really know. For what your doing I think I might just keep it stock on the stock shifter.

One of the reasons I have considered it is they say it makes my early model 4l80 a bit more reliable. There is a minor lubrication problem if your tranny cooler lines are right next to each other. Later cases they separated them to prevent this
 
Okay let me clarify first. I have never run one. Reverse valve bodies are usually full manual. I talked to someone about this once. I have been trying to remember who. but they said that it wasn't too bad daily driving. So the biggest reasons I see for going reverse valve body is to make it so you don't need a computer. Or to make it R and 1st right next to each other so you can hit reverse on a steep climb.

Other than that I don't really know. For what your doing I think I might just keep it stock on the stock shifter.

One of the reasons I have considered it is they say it makes my early model 4l80 a bit more reliable. There is a minor lubrication problem if your tranny cooler lines are right next to each other. Later cases they separated them to prevent this
Ok so yes the reason I want the reverse manual is to have the R and first next to each other and be able to manually shift to stay in control, not that I don't already have the computer.
I got the engine trans tcase with the computer and the whole truck wiring.
 
Like I said I talked to someone, a FMRVB. Told me it takes a bit of finesse with the gas pedal to get nice smooth shifts, but not really hard.

You can do that right Issam, shift with finesse :haha:
 
Like I said I talked to someone, a FMRVB. Told me it takes a bit of finesse with the gas pedal to get nice smooth shifts, but not really hard.

You can do that right Issam, shift with finesse :haha:
You have no idea.
I drove my 10 speed in my freightliner 10 years with a problem that I thought was minor, I finally needed a clutch so I take the transmission to be checked out.
The guy said you are lucky you didn't breakdown, the c clip holding the gears on the main shaft was gone and the gears could walk back and forth, I said I know it started 10 years ago and I just learned to baby it and lasted 10 years.
 
That is a cool 3/4 ton burb. I was thinking of getting a 3/4 ton Suburban like yours to put in a 1 ton dually drive train I have, and make the burb a 1 ton dually Suburban.

When it comes to those 4l80E's they do have some issues. Some of the issues where worked out by 1993, but some remained. The torque converter cast iron lock-up clutch pistons in those like to crack. I put a billit piston in my 4l80E converter to fix that. They also have excessive line pressure issues as well. A company called Sonnax have some pressure valves that can cure that. I put one in mine. The valve bodies also have some issues. The actuator feed bore on them have a tendency to wear out. I sleeved mine, which will fix the problem for about 100,00 miles until it wears out again. The steel check balls also like to gall the aluminum valve bodies. I replaced mine with Imidized plastic check balls from Sonnax. Sonnax also sells a complete valve body for the 4L80E that has all the known problems fixed, but they are pricey. The internal wiring harness on 4L80E transmissions like to dry rot and crack as well, thus causing all kinds of shifting problems. You should also replace all the speed sensors, shift solenoids (A & B), and converter lock-up solenoid (TCC solenoid) as well. There is another thing to improve the performance of a 4L80E called "dual feeding". You might not want to get into that unless you are going to rebuild the whole transmission.
 
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That is a cool 3/4 ton burb. I was thinking of getting a 3/4 ton Suburban like yours to put in a 1 ton dually drive train I have, and make the burb a 1 ton dually Suburban.

When it comes to those 4l80E's they do have some issues. Some of the issues where worked out by 1993, but some remained. The torque converter lock-up clutch pistons in those like to crack. I put a billit piston in my 4l80E converter to fix that. They also have excessive line pressure issues as well. A company called Sonnax have some pressure valves that can cure that. I put one in mine. The valve bodies also have some issues. The actuator feed bore on them have a tendency to wear out. I sleeved mine, which will fix the problem for about 100,00 miles until it wears out again. The steel check balls also like to gall the aluminum valve bodies. I replaced mine with Imidized plastic check balls from Sonnax. Sonnax also sells a complete valve body for the 4L80E that has all the known problems fixed, but they are pricey. The internal wiring harness on 4L80E transmissions like to dry rot and crack as well, thus causing all kinds of shifting problems. You should also replace all the speed sensors, shift solenoids (A & B), and converter lock-up solenoid (TCC solenoid) as well. There is another thing to improve the performance of a 4L80E called "dual feeding". You might not want to get into that unless you are going to rebuild the whole transmission.
Well you gave me enough ammo to go talk to the guys who will build it.
They usually do a good job of upgrading weaknesses in transmissions but not sure how far they go with the quote they gave me. $1800
I will find out when I talk to them.
 
There is a guy named Jake that owns a transmission shop called Jake's Transmission in Texas that seems to know the 4L80E trans as good as anybody alive. I learned a lot of what I know from some of his posts on the internet.
 
Jake's bypass box for the computer is a joke. You can do the same thing with the standard tranny plug and connecting a few wires. Plus that's full line pressure setup. Way hard shifts even at idle.

Transdapts kit with the vacuum modulator is way hetter IMO. I run it and it's smooth when I want and extremely rough when I want. That being said having all the parts to get it to shift automatically are way nice. Shifting all the time will get old on the street.
 
I run my 4L80E with the factory stock 7060 ECM/PCM and wiring harness. My GM TBI is a slightly modified bored out TBI by Vic Morse with an adjustable fuel pressure regulator. Once you start going to an aftermarket fuel injection system with its own aftermarket ECM, then that is a whole new ball game when it comes to what ever system you want to use to control the shifts on a 4L80E. Unless you want to just piggy back the aftermarket ECM with the stock ECM/PCM for a 4L80E.
 
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I run my 4L80E with the factory stock 7060 ECM/PCM and wiring harness. My GM TBI is a slightly modified bored out TBI by Vic Morse with an adjustable fuel pressure regulator. Once you start going to an aftermarket fuel injection system with its own aftermarket ECM, then that is a whole new ball game when it comes to what ever system you want to use to control the shifts on a 4L80E. Unless you want to just piggy back the aftermarket ECM with the stock ECM/PCM for a 4L80E.
Well the aftermarket mpfi system is supposed to run on the stock ecm and wiring.
I have not looked much into it and I am prepared to run the stock tbi system if I am not confident of the results with the new system.
I need to open the box and see what I got and start research.
I got this from @ChrisPerry so maybe he will chime in if he knows more.
 
So I think I am decided on engine choice.
Perkins td.
I got a good turbo for it and I will run a manual transmission and 241 tcase.
I can run my 32 spline 465 or if I find an nv4500 I will be better.
I will try and get the parts ready and rebuilt and after new years I get to put it together
 
I was just avenging beags, but yeah I can update here.
I am in the process of purging my collection of vehicles, donating one or 2 and hopefully selling a couple by the end of the year.
Then it will be parked and the rebuild of parts will begin.
My choice is set now and I will run my oil burner perkins T6.354 and I plan on a nv4500 behind it.
Which means I will not be able to whip that thing quick.
I will need to remove the engine crossmember and fab a custom one.
I already have a mockup from the k5 I had it in but I need to make a nicer one.
I also sold the 38" swampers so now I will be getting the 40" toyo on 17" rims.
My plan is to use the np241 behind the 4500, I realized that I will have a better crawl ratio than my k5 with the doubler.
And with the torque of diesel I am set
 

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