85threeofive
Registered Member
I have a 1985 305 K5 and I was wondering what kind of Tranmission that I had? I dont know if it is a 700-R4 or a TH-350 any help is greatly appreciated because I want to do a rebuild on it.
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Transmission question
- Thread starter 85threeofive
- Start date
700
85threeofive
Registered Member
how?
how can you tell?
how can you tell?
K5Steve
1/2 ton status
3 gears and an overdrive gear(4 speed auto).Does your gear indicator say
PRN(D)D21 or PRND21?The th350 is a 3 speed tranny.
PRN(D)D21 or PRND21?The th350 is a 3 speed tranny.
anjieandjohn
Registered Member
I have the same year and engine...and transmission and a 208 transfer case...I got under there the other day and cleaned off some of the road grime and dirt and actually found the id tag on the transfer case. The tranny could be a 700r4 but if you arent the original owner it is no telling. One way is to crawl underneath and look at the pan. A square pan w/ 16 bolts is the 700r4...LMC has a good picture of different transmission covers in it to help out as well.
XHitman396
1/2 ton status
K5STEVE's got it, if you have 1st gear, 2nd gear, drive, AND overdrive, it's a 700r-4, if only 1, 2, and drive, then it's a th-350, or a th400, but im not sure to tell the difference in those two....
roadnotca
3/4 ton status
tranny
Check me if I'm wrong, you've built engines before, maybe stick trannies; but not Automagic? If your's is a TH350 or TH400, GET and USE the book(s) by Ron Sessions and you will be rewarded bigtime. Do the beef-up, get a good Master kit like TCI so you can select 1,2 & 3, up and down (fantastic off-road). If it's 700R4, use it for a core. It took a couple of years for even the factory to get it right. Once they're done right, overdrive is kool, but spending that money might be better on an 80LE or whatever is the hot one now. Search in here for "700R4" and see what the consensus is. As you might guess, I've swapped-out my 700 for my built TH350 like above; 3000RPM at 70 MPH.
Check me if I'm wrong, you've built engines before, maybe stick trannies; but not Automagic? If your's is a TH350 or TH400, GET and USE the book(s) by Ron Sessions and you will be rewarded bigtime. Do the beef-up, get a good Master kit like TCI so you can select 1,2 & 3, up and down (fantastic off-road). If it's 700R4, use it for a core. It took a couple of years for even the factory to get it right. Once they're done right, overdrive is kool, but spending that money might be better on an 80LE or whatever is the hot one now. Search in here for "700R4" and see what the consensus is. As you might guess, I've swapped-out my 700 for my built TH350 like above; 3000RPM at 70 MPH.
85threeofive
Registered Member
thanks
All you guys frickin rock man, I cant tell you how much I appreciate the help. I just bought this truck with 81k original miles and in perfect running condition. Interior has a dash crack and 1 tear on the drivers carpet. Other than that, shiny black paint (when not muddy*) and Chrome rims with Cooper Tires. I've had 1991 and 1992 Firebirds and a Thunderbird Supercoupe so not to familiar with this truck yet.....Im not sure if I need a rebuild or not but it does shift hard in 1st-2nd, 2nd-3rd, but if u floor it u can barely feel it.
All you guys frickin rock man, I cant tell you how much I appreciate the help. I just bought this truck with 81k original miles and in perfect running condition. Interior has a dash crack and 1 tear on the drivers carpet. Other than that, shiny black paint (when not muddy*) and Chrome rims with Cooper Tires. I've had 1991 and 1992 Firebirds and a Thunderbird Supercoupe so not to familiar with this truck yet.....Im not sure if I need a rebuild or not but it does shift hard in 1st-2nd, 2nd-3rd, but if u floor it u can barely feel it.
roadnotca
3/4 ton status
85/305
The tranny pan will show which it is. Like I've said elsewhere, 700R4 is extremely picky about fluid level and TVS cable adjustment, make sure those are perfect, and then test. Let us know what u find.
1985 305 and 700R4, somebody thought they were getting an economy truck.85threeofive said:All you guys frickin rock man, I cant tell you how much I appreciate the help. I just bought this truck with 81k original miles and in perfect running condition. Interior has a dash crack and 1 tear on the drivers carpet. Other than that, shiny black paint (when not muddy*) and Chrome rims with Cooper Tires. I've had 1991 and 1992 Firebirds and a Thunderbird Supercoupe so not to familiar with this truck yet.....Im not sure if I need a rebuild or not but it does shift hard in 1st-2nd, 2nd-3rd, but if u floor it u can barely feel it.
The tranny pan will show which it is. Like I've said elsewhere, 700R4 is extremely picky about fluid level and TVS cable adjustment, make sure those are perfect, and then test. Let us know what u find.85threeofive
Registered Member
adjusment
How would I go about this, havent really dealt with a 700. I did a kickdown cable adjustment on my Thunderbird which was a AOD tranny, other than that, havent messed with Tranny's. BTW I filled up here in Steamboat at 2.45/gallon, 81 dollars
How would I go about this, havent really dealt with a 700. I did a kickdown cable adjustment on my Thunderbird which was a AOD tranny, other than that, havent messed with Tranny's. BTW I filled up here in Steamboat at 2.45/gallon, 81 dollars
roadnotca
3/4 ton status
700 Q
Its easy, but I don't have the book in front of me, but then you need to get it in print for yourself. Probably find it in CK5 search! Or you could go to PepBoys and read it, not even pay for the book.
$81 for gas, if its a truck, must be saddle tanks, or its a Burb w 40 Gal. tank.
Its easy, but I don't have the book in front of me, but then you need to get it in print for yourself. Probably find it in CK5 search! Or you could go to PepBoys and read it, not even pay for the book.
$81 for gas, if its a truck, must be saddle tanks, or its a Burb w 40 Gal. tank.
85threeofive
Registered Member
gas
K5 with a 31 gallon tank with high test gas
K5 with a 31 gallon tank with high test gas
Can Can
Pusher Man
Oh great........here we go again!!!!!
Can Can
Pusher Man
85- Welcome to CK5, brother!!! 
The best advice I can give you regarding your new aquisition is to swap out ALL of the fluids and every filter possible. Fluid condition is a really good way to tell what kind of shape the system you're checking is in.
As far as the tranny goes, regardless of what you're hearing, 700r4s are a great unit as long as you keep them clean and cool.
The best advice I can give you regarding your new aquisition is to swap out ALL of the fluids and every filter possible. Fluid condition is a really good way to tell what kind of shape the system you're checking is in.
As far as the tranny goes, regardless of what you're hearing, 700r4s are a great unit as long as you keep them clean and cool.
here some links
http://www.jeeptech.com/convtrans/gm/gm700r4id.html
http://www.highperformancecars.com/crosley/700id.htm
http://www.700r4.com/
thank you
stano
87 K5
http://www.jeeptech.com/convtrans/gm/gm700r4id.html
http://www.highperformancecars.com/crosley/700id.htm
http://www.700r4.com/
thank you
stano
87 K5
roadnotca
3/4 ton status
Trans
Check with Bowtie Overdrive. I think that's were I read about it, but the 350/400s had an iron pump, 700 was a switch to aluminum & they (GM) couldn't keep it flat (flat enough). The mail-order perf. 700R4 builders won't take cores, shipping would be a pain but they also have to select their cases & pumps. Like I said either this Forum or another, when done right, 700R4 works, but with the 60s & 80s out there, why bother w 700 if there is any problem with it at all?CanmoreK5 said:Oh great........here we go again!!!!!
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85threeofive
Registered Member
thanks bro
I appreciate all the help ive been given and will let ya know how it works out.
Again, you guys rock!
I appreciate all the help ive been given and will let ya know how it works out.
Again, you guys rock!
The only problem I had with the 700R4 that ::was:: in my blazer was the pump seal and bushing. Instead of replacing the seal and whatnot, I just swapped a TH400 and NP205 for the 700R4 and NP208. Never looked back 
700R4's are nice if you treat em right, don't overheat it. Flush, and change the filters when necessary. Get a Haynes manual, it tells you how to adjust the TV (or I can see about scanning it or something). There's a vent, I forget what it's called, or where exactly it is, but it's on the top of the tranny... sometimes it gets clogged and will cause leakage problems.
Lucas and any other 'tranny-fix' type fluids make your seals soft. Yes that helps with leaking and whatnot, but doesn't fix the problem, just prolongs the inevitable.
If you ask me, unless you really need that overdrive, I'd find a TH350 or a TH400 (preferably) for it instead of the 700R4. You'll need an adapter for the NP208, but if you can score a TH350/NP205 or a TH400/NP205 combo, it's a bolt-in replacement with only needing a longer rear driveshaft (at stock height that is).
If that 305 ain't enough, put a 350 in. It'll bolt up to the 700R4 without a problem (you can even put the 305 heads on the 350 for higher compression, ****ty flow compared to 350 heads, but you'll boost the compression on the 350).
I'd change your diff fluid too. Not too many 'regular' owners change that regularly, if at all.
700R4's are nice if you treat em right, don't overheat it. Flush, and change the filters when necessary. Get a Haynes manual, it tells you how to adjust the TV (or I can see about scanning it or something). There's a vent, I forget what it's called, or where exactly it is, but it's on the top of the tranny... sometimes it gets clogged and will cause leakage problems.
Lucas and any other 'tranny-fix' type fluids make your seals soft. Yes that helps with leaking and whatnot, but doesn't fix the problem, just prolongs the inevitable.
If you ask me, unless you really need that overdrive, I'd find a TH350 or a TH400 (preferably) for it instead of the 700R4. You'll need an adapter for the NP208, but if you can score a TH350/NP205 or a TH400/NP205 combo, it's a bolt-in replacement with only needing a longer rear driveshaft (at stock height that is).
If that 305 ain't enough, put a 350 in. It'll bolt up to the 700R4 without a problem (you can even put the 305 heads on the 350 for higher compression, ****ty flow compared to 350 heads, but you'll boost the compression on the 350).
I'd change your diff fluid too. Not too many 'regular' owners change that regularly, if at all.
roadnotca
3/4 ton status
What He said
And when you think about it, if you've commited to really heavy tires/wheels you need more HP & torque anyway, you can tolerate a net taller gear ratio, make it all turn slower at 75 MPH, if its all balanced right. I've seen a lot guys with mondo rubber on the highway @ 50 MPH, stayin just under the shimmies. Even more-so if you've got a doubler, let's see, trans in 1, front box in 4H, rear box in 4L; no wait front in 4L, rear in 4H . It all starts to be as much bling as the all chrome, don't get me dirty crowd, and thats not CK5. Figure the revs you want at 60 or 65, whatever, then build enough power to push that brick down the road. Face it, we gave-up economy when we bought a rolling livingroom. I can drive for hours on my bench seat, I'm given a rental when I travel and that bucket hurts after 30 minutes. Fullsize remember? We bought these because they're big and built like a brick crapper. And in a Burb, there's always a place to sleep, out of the mud.
And when you think about it, if you've commited to really heavy tires/wheels you need more HP & torque anyway, you can tolerate a net taller gear ratio, make it all turn slower at 75 MPH, if its all balanced right. I've seen a lot guys with mondo rubber on the highway @ 50 MPH, stayin just under the shimmies. Even more-so if you've got a doubler, let's see, trans in 1, front box in 4H, rear box in 4L; no wait front in 4L, rear in 4H
. It all starts to be as much bling as the all chrome, don't get me dirty crowd, and thats not CK5. Figure the revs you want at 60 or 65, whatever, then build enough power to push that brick down the road. Face it, we gave-up economy when we bought a rolling livingroom. I can drive for hours on my bench seat, I'm given a rental when I travel and that bucket hurts after 30 minutes. Fullsize remember? We bought these because they're big and built like a brick crapper. And in a Burb, there's always a place to sleep, out of the mud.
