700R4 and Correct Gearing

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Jrgunn5150

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I would suspect a governor, or valvebody tuning issue.
 

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I would suspect a governor, or valvebody tuning issue.

Agreed.

If it will run up through the gears just fine but won't do the same after a downshift, it's a trans problem.
 

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Close the 700r4 has the .70 od and the 4l80 is .75



with smaller tire cars and 410s the first gear of the 700 is basically for burnouts, not so much with 35s. There is a governor in the 700 that makes the transmission shift whenever it hits a certain rpm/centrifugal (IIRC) that over powers the springs and allows the trans to shift, putting in different springs will raise or lower the rpm for shift. It is located on the ps of the trans, is round and held in by s snap ring.

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driver side it where that governor is placed, there servo is on the pass side
 

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Maybe I am not used to hearing about cruising speeds for 500 horsepower motors but why would 2700 at 70 sound good to anyone if a modern 400 horsepower truck does 70 at around 1700 to 1900 rpm? I'm just curious because I am trying to make up my mind what the best gearset will be when I go to fine tune my LS swap (with 33's and a 4l60E)... It's the same OD gear as the 700r4 so I am trying to decide between 4.10's vs 3.73's. In my case I am looking for nice highway cruising, like as in daily driver cruising.
 

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Maybe I am not used to hearing about cruising speeds for 500 horsepower motors but why would 2700 at 70 sound good to anyone if a modern 400 horsepower truck does 70 at around 1700 to 1900 rpm? I'm just curious because I am trying to make up my mind what the best gearset will be when I go to fine tune my LS swap (with 33's and a 4l60E)... It's the same OD gear as the 700r4 so I am trying to decide between 4.10's vs 3.73's. In my case I am looking for nice highway cruising, like as in daily driver cruising.


its not they are just afraid of the 700r4 because they dont understand them/ had bad experience with a stock trans or stuck in their ways and will be complaining about mileage and wearing out stock engines at 100k miles for the rest of their life. Do the 410s The extra gear will help reduce load while cruising with the rpm at like 2k. I have 410s with 35s and its not great off the line and loafs along down the highway at 70, it kicks out of lock up for small hills, 373 with 33s should be similar. Or if you swap in a 4l80 you could keep the 373s as the 4l80 has a .75 od compared to the 60Es .70 that would put you just under 2k rpm for cruising and is much stronger.
 
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rpcraft

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its not they are just afraid of the 700r4 because they dont understand them/ had bad experience with a stock trans or stuck in their ways and will be complaining about mileage and wearing out stock engines at 100k miles for the rest of their life. Do the 410s The extra gear will help reduce load while cruising with the rpm at like 2k. I have 410s with 35s and its not great off the line and loafs along down the highway at 70, it kicks out of lock up for small hills, 373 with 33s should be similar. Or if you swap in a 4l80 you could keep the 373s as the 4l80 has a .75 od compared to the 60Es .70 that would put you just under 2k rpm for cruising and is much stronger.


I was thinking down the road of going with a 4l80 but it's just too much work to swap for now. I figure if I burn up the 4l60E I have then I will look into it more. I was hoping to avoid the shift down from the slight hills, like you mentioned. On my setup its an LS swap so the trans can be tuned to lock up a little different than the 700r4 but I think all things considered 4.10 is probably the best starting point for me with 33's. I have a 14 bolt FF and the bracket kit already and all the hard to find parts to swap the front to an 8 lug setup. The 14 FF came out of an 06 2500HD and has a 4.10 and a g80 in it. Just needs the pinion seal replaced and to be cleaned up and inspected (and brake lines, calipers, and rotors). I figured once I get it in the Jimmy I could just leave the front driveshaft disconnected for now and test driving, weld up the brackets on the 14B and if I don't like it then it is far easier to swap 3.73's on an open diff in a few hours and test out how I like the difference for comparison, and then once I settle on a ratio I can pickup a spare 10 bolt front and do a fresh rebuild on it to match the gearing and then it will be ready to driveway swap over a weekend.
 

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You dont have to remove the front drive shaft unless you are full time 4wd/awd whatever they called it, although its good insurance you wont accidentally knock it in 4wd.
 

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I'm not worried so much about me doing it or about it accidentally going into 4wd. I'm worried about other family members who do not pay attention to things I say, lol. Call it a life lesson if you will.
 

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Maybe I am not used to hearing about cruising speeds for 500 horsepower motors but why would 2700 at 70 sound good to anyone if a modern 400 horsepower truck does 70 at around 1700 to 1900 rpm? I'm just curious because I am trying to make up my mind what the best gearset will be when I go to fine tune my LS swap (with 33's and a 4l60E)... It's the same OD gear as the 700r4 so I am trying to decide between 4.10's vs 3.73's. In my case I am looking for nice highway cruising, like as in daily driver cruising.

Because the original truck in this thread has very different wants and needs than a new truck. That 2600/2700rpm was without functioning lockup too. A 500hp 350 with a lopey cam is not going to like pushing a 4500 lb brick down the interstate at lower rpms. Especially if it's supposed to be a 'fun weekend' truck. Taller gearing would take all the fun out of it, and the lugging would not be kind to mpg either.

But yes, OD with 4.10 and 33's makes for a nice all-around combo with the average mild FI Chevy v8.
 

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