700R4. Love it or hate it?

[djw32]

Originally Posted by Andy4639

Yea it does that. It has a habit of being on empty all the time. I can get about 600 miles out of a tank of gas though if it's all interstate driving and I stay under 70. I drive it to the beach for the spring car show and it's 300 miles one way for me and I can go down and back and forth to the show and then head home before I fill up though.

Oh yea I got a 40 gollon tank in it though!!!

This is a great thread.

Andy,
Do you have a picture of that 40 gallon tank? Did you mount it in the bed?

[texanidiot25]

Originally Posted by 70onB.A.D.'s

Hey guys another question. How bad is the gas mileage on the highway with the TH350 or should i look for switching out to a 700r4 or will a 4L60 work?

The TH350 is horrible on the freeway. I can't cruise more than 65 really. Of course I can go faster if I wanted, but as far as cruising, I'm in the slow lane... In fact I get far better city mileage than highway. But I also have 4.10-ish gears..

[Andy4639]

2nd_wnd

i don't really care for mine. it was rebuilt and setup so convertor locks up automatically in 2nd, 3rd, and od.
Plus i only have 3:08 gears . I miss the th350 i had in it. Would trade it out to anybody that has a TH350 and a place to swap it

Why do you have it locking up in 2, 3 rd gear? I only have mine lockup in drive when I'm going over 45MPH. I have a manual toggle switch I can leave it out of lockup if I want also.
This is why your truck is always searching for gears it's bumping in and out of lockup.

[67ChevyRedneck]

I may be wrong, but I believe in "stock" form the 700R only locks in 3rd and OD.

[72chevyk10]

Originally Posted by texanidiot25

The TH350 is horrible on the freeway. I can't cruise more than 65 really. Of course I can go faster if I wanted, but as far as cruising, I'm in the slow lane... In fact I get far better city mileage than highway. But I also have 4.10-ish gears..

thats usually me but last weekend i drove 50miles at about 60-70mph and i got about 12.5 mpg. i was shocked! i got 4.10ish gears too (and 35in tires probly helped with that)

[Critter]

A little off subject, but I remember something about the 200r not being able to mate with a transfercase, aka, a 4x4 application. Am I making this up or IS it possible using GM parts?

[Hertzdaddy]

FYI, here's an article about the 200-4r that supports what some have already said here.

http://www.carcraft.com/techarticles...ild/index.html

Couldn't find this article right away but here it is now. Some conflicting opinions.

http://www.webrodder.com/article.php?AID=426&SID=6

Eric

[68shortstep]

Originally Posted by 67ChevyRedneck

I may be wrong, but I believe in "stock" form the 700R only locks in 3rd and OD.

That's right, I'm pretty sure. No overdrive in 1st or second if a stock trans.

I had a nasty-colored (yellow/tan/yellow/tan) '85 Silverado when it was brand new, that I absolutely-hated, because it was always see-sawing in & out of gears between overdrive & third, going up long gentle-slope hills. Got lotsa those in this part of Arkansas.

Then somebody told me: Hey dumb*ss, just set the transmission gear selector pointer on the "D" marker, & not the D with the "O" around it, unless you're out on flat highway/freeway....... you'll burn the trans up with all that pointless shifting, & it won't go into the overdrive at all unless you use the "O" marked drive pointer.

All was better then.

I guess that would be the purpose of a manual lockout / engage switch after a trans swap.

Sure made a big difference to me in how much I liked the truck.

Maybe I should have read the owners manual, or something, too ??????

We later had a '92 Buick Roadmonster (that's the color I used for my pickup) with the same 350 engine & 700 OD trans in it, that my wife drove most of the time, and we hardly ever used the overdrive, unless out on the road on long trips. Same "see-sawing" in & out of overdrive, otherwise.

[67ChevyRedneck]

^700R's are NOTORIOUS for wanting to shift in OD early. With light acceleration mine will shift into OD at about 40-45mph. Way too slow of a speed. That's one of the reason's I love my Lokar floor shift. I drop it into 3rd and leave it there until the truck hits about 50mph or so, then I bump it up into 4th. If I do city driving where I almost never hit much over 40-45mph I just leave it in 3rd.

[Critter]

Originally Posted by Critter

A little off subject, but I remember something about the 200r not being able to mate with a transfercase, aka, a 4x4 application. Am I making this up or IS it possible using GM parts?

Originally Posted by Hertzdaddy

FYI, here's an article about the 200-4r that supports what some have already said here.

http://www.carcraft.com/techarticles...ild/index.html

Oh that's right, 200-r4 don't have a removable tailshaft. I knew I wan't loosing my mind.

[Mixup]

Love it. It's been in my truck almost 7 years.

[charlie diaz]

I may be reading it wrong, but I think that there is some confusion on what the lock up does. The electric lock up locks up the converter electronically once the tranny is in OD, or in 3rd if you just have it in D. The locking mechanism is designed to reduce slippage of the tranny for lower RPMs which will in turn give you better MPG. with the lock up set up on a switch, then you can lock it up when you are in 3rd for when you are towing. You're obviously not going to tow in OD. You can still go into OD without the lockup, but you will have slippage and eventual failure. I'm not trying to steal the thread, I just thought that this was pertinent information.

[6772owner]

I have my trans set up with the Jet Performance vacuum switch kit and have no problems what-so-ever with the locking/unlocking of the torque convertor, seems to operate as it should to me, basically seemless til you hear the RPM's drop.

[weircc]

well this thread has helped me decide on the route im gonna go i have been looking at 700r4 to purchase for awhile.i have been looking on ebay and there seems to be some reasonable pricing on there. so i think but not sure they are selling up to 500hp 600 pounds of torque for like 850.00? deal or no deal?

[tekno62]

I searched but didnt fond anything meanful

you have a link for the Jet Performance vacuum switch kit

Originally Posted by 6772owner

I have my trans set up with the Jet Performance vacuum switch kit and have no problems what-so-ever with the locking/unlocking of the torque convertor, seems to operate as it should to me, basically seemless til you hear the RPM's drop.

[pmpski_1]

Originally Posted by weircc

well this thread has helped me decide on the route im gonna go i have been looking at 700r4 to purchase for awhile.

My hope was to help me decide one way or the other, happy to see it's helped others too!

[sweet70beast]

Originally Posted by charlie diaz

I may be reading it wrong, but I think that there is some confusion on what the lock up does. The electric lock up locks up the converter electronically once the tranny is in OD, or in 3rd if you just have it in D. The locking mechanism is designed to reduce slippage of the tranny for lower RPMs which will in turn give you better MPG.

Accually the lock up of the torque converter reduces heat. When a torque converter "slips" it creates alot of heat in the tranny fluid, heat will break down the fluid. More heat faster the break down of the fluid. By locking the torque converter it acts like a presher plate/clutch assembly for a manuel trans, buy physically locking the output of the engine and the input of the trans so they are spinningv the same speed. If the tranny fluid breaks down because of the heat it will sooner or later toast the trans. That's another reason the TV cable set up is so important, if it's set wrong the internals of the trans slip causing the same heat then failier.
Locking the torque converter does get you little better milage it is not the reason for it. A slipping converter can spin anywhere from 200 rpm to 700 rpm slower than the engine, by locking them together they spin at the same rate causing the effecientcy (milage) to go up slightly.
I personaly love the 700r4, I am going to put one in my 71 K20 this summer. I had one in my 70 Nova for a while and hated it. My Nova has 3.08 rear and I was using more gas with the 700 than I was with the th350 that was in it before. I am switching to a 3.73 rear when I put a T5 in it. I wouldn't go any higher than a 3.73 unless the engine is fuel injected. Some cars run 3.08 or 3.42(from the factory) with 700r4 but they are usually fuel injected.

[Dying2Live]

I have a 700r4 behind the 350 in my S10, with 3.73s. I love it, but I was happier with it with the 3.08's in it because it held 2nd gear longer. My only gripe about the 700r4 is that it won't upshift into OD at WOT. In fact it won't upshift past about 75% throttle. On police cars they do, but not the others. They make an aftermarket valve body that allows them to upshift at WOT, I just haven't bought one yet. Other than that I love my R4.