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6.5 auto to 5-speed stick, easy?

DieselSlug

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Ok, i wanted to rebuild my 4l80e, but i have an ption to buy a complete "kit" to change my truck over to 5-speed. How hard is it? What has to change? Will the pedals bolt right up to the firewall? How does the slave cylinder function? Will this piss my pcm off? I have always wanted it to be a 5 speed. I have 3.42 rear gears, are the 5 speed gears better than the autop gears? My auto tranny has 206k on it and im sure iot wont last 50 more with all the plowing it does. I dont mind plowing with a stick, done it before, can do it again.... Please let me know!!!!! THe manual tranny has 125k on it and shifts flawlessly.. Will my driveshaft and t-case work with the manual? Is the crossmember different?
 
I spent $2,500 to get my 4L80 rebuilt and I could of changed over to a 5 speed for a lot less. And I should of done it! Everything is a very easy bolt in. Just goes in the factory places. Driveshaft should be the same length is what my transmission shop told me. You will have the full manual control of each gear which is very good with the exhaust brake. Heath can redo your computer. Your 3:42's will be great. I went to a very tall tire and my gear ratio is now in the 3:48 area.
 
It's not a bad job to do if you have the donor truck as well to get all the little parts.
Is it a 3500 or a 2500? 3500's had different t cases depending on year which may affect driveshaft length. But if you take everything it will not matter. Can you get the comlum and the dash as well? Swapping them will make the truck look factory
 
I do have cruise.. But isnt that computer controlled? Cant i really leave my column in until i get time to take it out? I will get the correct column in the sale tho.. Im pretty sure the t-case is included. I was most worried about the pedals bolting to the firewall.... I sent him an email, i will tell you guys as soon as i find out. Thanks!! Keep the advice coming!!!
 
Me thinking out loud here.

It might be easier to swap out a truck cab that is a five speed, than trying to install all the goodies to turn your truck into a five speed.
 
Me thinking out loud here.

It might be easier to swap out a truck cab that is a five speed, than trying to install all the goodies to turn your truck into a five speed.

Me agrees!

I think it would be easier to sell the truck and buy a 5 speed equipped one.
 
Ok, still dont know if i can just bolt the pedals up, if i can then i will do it, but if not than i dont have the time to replace the whole dash. Cant sell the truck, sentimental value.... (deceased g-pa's truck)...
 
For the pedals there shouldn't be a problem with swapping pedal assemblies. The 4 studs that go through the firewall hold the brake master cylinder and AFAIK there is only one master cylinder.

The clutch slave cylinder will take a little dremel work. It is a twist lock setup at the firewall. You will need to drill a hole and cut notches for the wings. The flat spot for it should already be there.

You also would need to get the trans wiring harness. That will likely be different. It only has Neutral safety switch, backup light switch and speed sensor.

I would think cruise control wouldn't be affected by the swap.
 
On the trans wiring harness, is it part of the main harness for the truck? Or does it just plug in somewhere under the truck to the main harness?
 
When I did mine I had to get the clutch pedal and bracket from the bone yard. Then there is a small bracket spot welded to the firewall but I made my own with a piece of 1" piece of square tubing. The vss and comp are all fine fine with the change with the exception of the chip. You MUST change the chip to a manual chip instead of auto chip. I didn't for a awhile and milage, power etc sucked..... My advice find out what pump you have call Heath with the info pump, gvw, manual trans, year etc and put in his chip when you change the trans. I would also go with a 97 and newer slave cylinder, the input shaft goes thru it ( NO fork to mess with) I had to move the carrier bearing an 1" because nv4500 and 4L80e are not same length. In my opionion i would do it again not that bad of a job. I have some GM part numbers if you want them just let me know.
 
I would also go with a 97 and newer slave cylinder, the input shaft goes thru it ( NO fork to mess with) I had to move the carrier bearing an 1" because nv4500 and 4L80e are not same length. In my opionion i would do it again not that bad of a job. I have some GM part numbers if you want them just let me know.


I do plan on getting a GL4 chip for this truck. Please explain more about the fork thing. I had a 94 silverado 5-speed and the rod went through the firewall into the slave. So the clutch pedal will have a spot already made for it under my dash? Why did you make one if one is already there? The smaller brake pedal will also work where my larger one goes? Now since the nv and 4l80 are different lengths if i got the t case and driveshaft off the 3500 i shouldnt have a problem, right? Do you have any pics of the truck you did the swap on? Showing the kind of stuff you had to do? thanks so much for your insight!!
 
The early style slave cylinder is external and has a fork like the old manual clutches. The newer ones have a slave cylinder that goes around the snout of the tranny.

Personally I'd rather have the early style because you don't have to pull the trans and transfer case if the slave cylinder goes bad.
 
Im having second thoughts... I just dont want to get the stuff and im missing parts and crap. I should just buy a junk truck with a 5 speed to convert it...
 
Im having second thoughts... I just dont want to get the stuff and im missing parts and crap. I should just buy a junk truck with a 5 speed to convert it...

Mike, I got your message and was going to call you back, but got busy with the kids this weekend.

I agree that this would be the best idea. You would get ALL the parts you need, -and you have no questions about how the stuff is supposed to go together (not that you couldn't figure it out) -but having it all together in front of you saves a lot of guesswork for sure.

It would be cool, but it would require a fair amount of time.....
 
Mike I can take pics of anything you want. Maybe even a road trip if you aint to far.
On edit mapquest says 5 hours.
 
I dont know what to do, i really want to do the swap, i told him to measure up the driveshaft n stuff.. If the pedals mount up as an assembly that would take some hastle out of it. The next thing i would need to worry about it the driveshaft and tcase legths.. WOuld my t case work? Would i just need his driveshaft? Due to the nv4500 being a little shorter? I dont know what to do.. There is no one around here i can compare to.... The only other 6.5 ive seen is an auto like mine and 1/2 ton.
 
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My t case and shaft were/ are fine. 4 years later no prob just had to move carrier bearing. I would do the swap it doesn't take too much to do. The brake pedal is easy there is a pin that holds them in just pull it and put in the little pedal. The only thing is the mounting bracket for the clutch pedal. I had the dash out of mine it made that al the easier. I'll try and get you some pics soon.
 
I was starting to add up the price of everything today...

Manual transmisson starter...
Cost of tranny and parts....
One piece flywheel to replace the two piece job...
Fuel to go get all this stuff...

I could rebuild my 4l80e for all that......:mad2: I really want to do the swap, but from the cost aspect it doesnt seem practical....
 
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