Transmission interchangability...

. . . . Transmission interchangability... Group: alt.autos.4x4.chevy-trucks Date: Sun, Oct 26, 2003, 6:39pm From: shades snipped-for-privacy@netins.net (Shades)

=A0=A0Will the TH700R4 from an '88 3/4T 4x4 fin into an '85 Suburban

My "'Burban originally had a 700 and I swapped in a TH350 using an adaptor.

It was a desperation move! I aint complaining, it works AWESOME! The thing is, the friend of mine that just bought the truck doesn't want the 700 and I need one with 4.10 gears.

All he will be using the truck for is to tow his skid loader and push snow. So I offered to swap him straight up trans for trans. BUT, only if they will swap straight up...

=A0=A0=A0=A0=A0=A0Any help on this?

if there will be ANYTHING more than R&R, I aint gonna do it! I know I will need a lock-up kit if I wanna use that feature(I took the few electronic items out of my 'Burban)! =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D Shades, as long as all you did was change out the tranny using the th350 conversion....the only things you need to worry about is the following.

Bell housing bolt pattern, conditional upon each trucks engine type.

Throttle valve cable must be reinstalled.

Lockup must be hooked up to keep the unit from overworking.

I would suggest you consider this trade out very carefully before you do it. The price difference between rebuilding a TH350 and a 700R4 is several hundred bucks, as much as 6-8 hundred dollars difference, depending on who you ask.

any whooo...... as long as you can still hook up the tv cable to your carb linkage, you wire in the lock-up, and the engine sizes for the bolt pattern are the same.......you will be okay with everything else.

marsh ~:~

Thank you, Marsh! Yes, all I did was buy the adapter(the aluminum 'filler' between the trans and the t-case) for the 700-350 swap and used a short-shaft 350 and cut, I think it was, 1 1/8 inches off the output shaft. As far as power-plants go. I have a 350 and his has a 6.2 diesel... Will this be a problem? Thanx again Marsh...

Transmission interchangability...

Group: alt.autos.4x4.chevy-trucks Date: Sun, Oct 26, 2003, 6:39pm From: shades snipped-for-privacy@netins.net (Shades)

Will the TH700R4 from an '88 3/4T 4x4 fin into an '85 Suburban

My "'Burban originally had a 700 and I swapped in a TH350 using an adaptor.

It was a desperation move! I aint complaining, it works AWESOME! The thing is, the friend of mine that just bought the truck doesn't want the 700 and I need one with 4.10 gears.

All he will be using the truck for is to tow his skid loader and push snow. So I offered to swap him straight up trans for trans. BUT, only if they will swap straight up...

Any help on this?

if there will be ANYTHING more than R&R, I aint gonna do it! I know I will need a lock-up kit if I wanna use that feature(I took the few electronic items out of my 'Burban)! =========== =========== Shades, as long as all you did was change out the tranny using the th350 conversion....the only things you need to worry about is the following.

Bell housing bolt pattern, conditional upon each trucks engine type.

Throttle valve cable must be reinstalled.

Lockup must be hooked up to keep the unit from overworking.

I would suggest you consider this trade out very carefully before you do it. The price difference between rebuilding a TH350 and a 700R4 is several hundred bucks, as much as 6-8 hundred dollars difference, depending on who you ask.

any whooo...... as long as you can still hook up the tv cable to your carb linkage, you wire in the lock-up, and the engine sizes for the bolt pattern are the same.......you will be okay with everything else.

marsh ~:~

yes

the diesel torque converter is an entirely different animal than a converter for a gas rig

plus the wiring in the pan is vastly different

Different how with the converter??? And as for the wiring, what could be different? The only electric or electronic item is the lock-up and that could be run by a toggle switch!

I think he's using wiring as a euphemism for the hydraulic circuits in the valve body. a diesel's TC will have a significantly lower stall speed than a gasser and the tranny's governer and shift points need to be set for the diesel's much much lower redline.

-Bret

power-plants

message

it's pretty apparent that he's never seen all the different wiring diagrams for 700's...............over 20 total, depends on year, model, engine, etc etc etc etc

if he wants to e-mail me with an address, I'll send him a copy of a tech bulletin that details the wiring diagrams, plus a trans model (that's what those labels loke '7TKM' stuck to the top of the bell housing mean) vs vehicle print-out (40 pages or so)

the same goes for anyone else that's interested, please use the subject line 'request for 700 info' so I can use a 'message rule' to shunt them into a separate folder

WHAT IS DIFFERENT WITH THE TORQUE CONVERTER? Please! What will the difference between the wiring mean when it comes to an aftermarket, stand alone lock-up control?

stall speed and some had a 'poppet valve' arrangement to kick it out of lock-up when decelerating

various models use prresuure switches in series with the solenoid coil, to enable or delay loch-up until certain conditions

my offer of the 700 information is open to all, just send me an e-mail with a subject line of 'request for 700 info' along with a mailing address

Gary, so basically everything will work, Right? Stall speed being low is fine! No lock-up decelerating is fine! As long as the lock-up will work with an aftermarket, stand alone lock-up control and the converter will bolt up, its all good!!! Anything else that will allow the 700 to not FIT into and BOLT up and OPERATE in my gas 'Burban?

in

news: snipped-for-privacy@storefull-2312.public.lawson.webtv.net...

OK

I'll say it once more

you DO NOT WANT a diesel converter behind a gas engine

been there, tried it, it doesn't work worth a crap

buy a remanned converter from Precision of New Hampton, IA

model 4842G, or 4842RV if you plan to tow

wrote

. . . . Oct 28, 2003, 7:33am From: shades snipped-for-privacy@netins.net (Shades)

=A0=A0=A0=A0=A0=A0Gary, so basically everything will work, Right? Stall speed being low is fine! No lock-up decelerating is fine! As long as the lock-up will work with an aftermarket, stand alone lock-up control and the converter will bolt up, its all good!!! =A0=A0=A0=A0=A0=A0=A0=A0Anything else that will allow the 700 to not FIT into and BOLT up and OPERATE in my gas 'Burban? =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D Shades, Gary's telling you that if you use that diesel tranny in your truck with the diesel convertor..

YOU CAN INSTALL IT.....it will work.... but......

you're gonna feel like your trying to plow through a field of Biscuit Batter.....

absolutely complete loss of lower end take off.......and accelaration.

you're gonna think your towing a house down the road...on it's foundation.

Maybe a little overdramatic...but damn close to what your gonna feel after switching out from the TH350 setup.

You said.....if it's ANYTHING more than just an R&R swap out....you wouldn't even consider it.

Well.....consider this.....your fixing to swap out a sturdy TH350 that costs about $900 to REPLACE if the thing ever takes a total sheet on you, and that's with the shop doing ALL the work. (please note ..i said replace)

That 700R4 that's been used in that diesel, maybe driven hard and put up wet, is going to cost you a minimum....of $900 on the bench with you taking it out.....and bud...that's minimum. The price very apt to be around $1200-$1400 on the bench for a class act overhaul.

I'm telling you Shades.....unless there's a reason that you just don't want that TH350, other than gas mileage,.....don't do this thing bud....you're gonna be posting in here within a year or so begging Gary to take one up the ole wazoo for you.......

Think it over ...real good....

gas ain't cheap, but is it worth the extra $6 a week savings to go through all that headache?

That 350 is gonna last forever unless you dawg it out....and even if you do...it's gonna last a hell of a lot longer than that 700r4, that you're taking your friends word for...hasn't been a problem...in how many miles??

respectfully,

marshmonster ~trying to keep a bud from jumping off the roof~ =3D=3D=3D=3D=3D=3D =3D=3D=3D=3D=3D=3D

Oct 28, 2003, 7:33am From: shades snipped-for-privacy@netins.net (Shades) =A0=A0=A0=A0=A0=A0Gary, so basically everything will work, Right? Stall speed being low is fine! No lock-up decelerating is fine! As long as the lock-up will work with an aftermarket, stand alone lock-up control and the converter will bolt up, its all good!!! =A0=A0=A0=A0=A0=A0=A0=A0Anything else that will allow the 700 to not FIT into and BOLT up and OPERATE in my gas 'Burban?

TOP POST....

Marsh, back when I had the first trans in my '88 K2500 I could only run it in drive as the TC would chatter like a bastard when it locked up, anywho, when I finally replaced the trans, I went from spending $45 a week in gas to $25 in gas. 20 bucks a week is alot to save when you're only going 250-300 miles.

-Bret

Gary, so basically everything will work, Right? Stall speed being low is fine! No lock-up decelerating is fine! As long as the lock-up will work with an aftermarket, stand alone lock-up control and the converter will bolt up, its all good!!! Anything else that will allow the 700 to not FIT into and BOLT up and OPERATE in my gas 'Burban? ============== ============== Shades, Gary's telling you that if you use that diesel tranny in your truck with the diesel convertor..

YOU CAN INSTALL IT.....it will work.... but......

you're gonna feel like your trying to plow through a field of Biscuit Batter.....

absolutely complete loss of lower end take off.......and accelaration.

you're gonna think your towing a house down the road...on it's foundation.

Maybe a little overdramatic...but damn close to what your gonna feel after switching out from the TH350 setup.

You said.....if it's ANYTHING more than just an R&R swap out....you wouldn't even consider it.

Well.....consider this.....your fixing to swap out a sturdy TH350 that costs about $900 to REPLACE if the thing ever takes a total sheet on you, and that's with the shop doing ALL the work. (please note ..i said replace)

That 700R4 that's been used in that diesel, maybe driven hard and put up wet, is going to cost you a minimum....of $900 on the bench with you taking it out.....and bud...that's minimum. The price very apt to be around $1200-$1400 on the bench for a class act overhaul.

I'm telling you Shades.....unless there's a reason that you just don't want that TH350, other than gas mileage,.....don't do this thing bud....you're gonna be posting in here within a year or so begging Gary to take one up the ole wazoo for you.......

Think it over ...real good....

gas ain't cheap, but is it worth the extra $6 a week savings to go through all that headache?

That 350 is gonna last forever unless you dawg it out....and even if you do...it's gonna last a hell of a lot longer than that 700r4, that you're taking your friends word for...hasn't been a problem...in how many miles??

respectfully,

marshmonster ~trying to keep a bud from jumping off the roof~ ====== ======

Oct 28, 2003, 7:33am From: shades snipped-for-privacy@netins.net (Shades) Gary, so basically everything will work, Right? Stall speed being low is fine! No lock-up decelerating is fine! As long as the lock-up will work with an aftermarket, stand alone lock-up control and the converter will bolt up, its all good!!! Anything else that will allow the 700 to not FIT into and BOLT up and OPERATE in my gas 'Burban?

I've seen some of the wiring before, just didn't feel like sticking my foot in it. Actually have seen people who did a 350/700 swap who decided to do some wiring changes. Not only that.... (not to Gary) have you EVER taken a tranny pan off? There's more wires than scribb has comments....

~KJ~

Gary, stop offering their services. They will not sell to individuals. Unless you want to offer your services as an intermediary transmission shop to purchase, and drop ship?

~KJ~

What are the differences between the 350, 400, and 700 trannys? Why is the

~KJ~

I'm sure Gary can give the details, but here's the basics..

the TH350 and TH400 (3L80) are 3 speed non overdrive vacuum modulated transmissions that came with or without lockup convertors.

the TH700-R4 (4L60/4L60E) is a 4 speed overdrive throttle valve (4L60) or electronically (4L60E) modulated transmission with a lockup convertor (did the very early ones come non-lockup,G?)

a TH700-R4 is more or less the same strength as a TH350 when the selector is in "D". it is weaker (in stock form) when in OD because the road simply has leverage over the input shaft. there were huge probs when the 700-r4 first came out because it was one of the very first 4 speed autos put into a truck and ppl simply didn't know their limitations. properly built, a 700 is plenty strong although it'll never be as strong as a built TH400.

HTH, Bret

I've heard the OD wasn't very strong on them.

My new TH700R4 has "automagic" od. My old one had the D with a circle around it. Dunno if I like that one......

How obvious should it be/feel when it locks up, or goes into OD (is OD locking up, or is there a "fifth gear" with a ratio of 1:1)

Much confused about locking upness. A tc can lock up, and a tranny as well? Whets the point of the TC not locking up, isn't that where the 5% or so is lost on highway? Why bother to "lock" a tranny, when you could just have a

~KJ~

a couple of additions in-line

the 400 never came OEM with a lock-up

no

the early 200's and Th-125 (front wheel drive) were non-lock-up, but the 700 has been a lock-up from Day One

I explain it as a see-saw, with the long end occupied by the truck's mass, the short end by the engine torque, and the pivot point is the rear planet set, which is what usually goes first

actually, the rear planet is in OD mode in both 2nd and fourth

I prefer the 350 or 700 over the 400 because there is no problem with leakage in the oil circuits between the case and center support, which is the 400's down-fall

Also, the stock 400 converter is a bit 'doggy' off the line, but using an Allison 540 converter cures that problem.

strength is relative...

actually 3rd gear is 1:1, OD is .70:1 It should be fairly obvious when the TC locks up, if you've got 3.73 gears it should lock up at about 40 MPH cruising. if you have a modified exhaust, lockup can be heard when the engine stops "droning" and individual exhaust pulses can be heard. OD isn't locking up, "locking up" is when the ECU (Engine Control Unit) activates a solenoid in the pan which allows fluid pressure to press a clutch against the front cover, eliminating any slip in the convertor.

no, Lockup is the elimination of TC slip.

the point to locking the TC is to save gas. with the convertor locked, the engine will be turning 200-400rpm slower (depending on load). your final drive will be 0.70:1 in a 700-r4, also slowing the engine RPM's saving an assload of gas.... around 30% better mileage.

-Bret