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bnoon
02-01-2005, 07:09 AM
<snip>
early/pre ~87 700R4=should be avoided like the plague.
late 87-92 700R4=non computer controlled (cept for TC lock up) 4spd OD trans.
4L60E=same trans but computer controlled as well as TV calbe control.
4L65E= ditto here but no TV cable and 100% puter controlled (correct me if Im wrong its early in the AM).

The list of trans's above have durability updates the newer the unit is and in most instances the newer hard parts will retro fit into the older units. Im running GM 5 gear planets for the 65E in my 91 700r4 right now after shattering the older 4 gear units...twice. Personally, I dont recommend the 700 to be used in anything that makes 425ish ftlbs of torque and can put that power to the ground. At around that level its not a matter of if it will break but when and the more torque you put through it the shorter its life gets. IMO the 700s internals just cant be made strong enough to reliably handle high HP for any length of time no matter WHO builds it or what kind of magic dust is sprinkled on it (yes, Ive spoken to the REAL Art Carr and he hates the 700 too).</snip>
Here's a snip of a quote from mycyclone. Can anyone tell me why to avoid the pre '87 700R4's? The '84 and previous trans was the one to avoid I thought because of the 27 spline input shaft vs. 30 spline for '85+... Or was that the "~" before the 87 that he means he didn't know what year they went to the 30 spline? Do the 5 gear planets still fit the '86 I have? Is that the weak link? I will only have around 400 HP/TQ with a nice trans cooler and heavy duty frictions, but I want it to last. The car will never see slicks, but it will see the occasional blast down the quarter with street tires.

myclone
02-01-2005, 04:37 PM
Mid 87 is when the 30 spline input shaft started showing up on a regular basis so an early 87 will prolly have 27 splines. Its a crap shoot on 87s though as you can find either one for that year so the only way to know for sure is to check the input shaft (Ive found 30 spline inputs in early 87s and 27 spline in late 87s before). All 88 and newer 700s Ive gone through had 30 spline input shafts.

The 5 gear planets will retrofit all the way back and be sure to buy GM planets as the off shore knock offs like whats sold on ebay are weaker than even the old GM 4 gear planets. Theres a reason ppl can sell new 5 gear planets for ~90 bucks.

Use a ten vane pump (13 isnt needed and a few ppl have had issues).
Install a .500 boost valve.
Install an extra spring from Sonnax to hold the pump at full volume 100% at any RPM.
Reverse input drum MUST be flat where the 2-4 band applies.
Install a 093 vette/hipo 2nd gear servo.
Air check the input drum once its assembled as a lot of times they leak where the input shaft goes in the drum (if it leaks get another input drum).

I dunno if youre going to rebuild the trans or if a shop is gonna do it but if youre doing it then there are a lot of other little things that can be done to firm up the shifts to the point of being brutal if you want. I can list them if you want but if a shop is doing it then they prolly already know all the "tricks". BTW, Im not a big fan of kevlar for friction material as the coefficient of friction of kevlar is fairly low. Yeah, itll withstand heat but it also allows more slippage than regular red or blue frictions which adds heat. To get kevlar to hold in a hi po application as well as the regular frictions you have to hit it so hard with lots of line pressure seals start to blow off and stuff starts to break from the fluid pressure.

Oh, at 400hp/ftlbs and with street tires a properly built 700 will prolly last you quite a while if its subjected to only a hand full of passes at the strip per year and spirited street driving. Just remember than autos are just like a sticks clutch pressure plate and T/O bearing in that they do require freshening after a certain amount of abuse/miles.

bnoon
02-01-2005, 06:02 PM
FYI... one fact I do know is that late '84 to early '85 was the switch over year for 27 vs. 30 spline, at least in F body cars. I've replaced the converter in my car and I have a spare '86 trans from a friend's '86 Trans Am parts car, both 30 spline. The thirdgen.org site and forums would confirm this info for argument's sake, but the site has been down since last week...

Thanks for the rest of the tips though. Some good info in there! The only thing I've heard about up to this point was the vette servo and a few line pressure mods... I will be doing the rebuild myself and it's my first 700R4/4l series rebuild, but I have been into auto transissions before TH350/400/C4/C6 etc, so at least I know the theory behind the bits involved.

I don't need the "brutal" tricks though. This car will be mostly a street car for cruise nights and such. Thanks!

myclone
02-02-2005, 05:24 AM
I'll have to go back and check my info on when GM decided to start using the 30 spline input shaft but like I said Ive found 27 spline shafts in units up through late 87. The units could have been gone through before I got hold of them though so that may explain that in some or all the cases. FWIW/BTW, the GN/Turbo Buicks use the same small 27 spline input shaft on their 200R4 which has gone low tens fairly reliably so the small shaft isnt a huge issue as much as the early slush boxes not having a proper lube set up and/or pressure for hi po use as well as other fairly weak parts.

In general the later the unit the more updates or factory "fixes" will have already been done for you from the factory like one piece apply plates versus failure prone multi piece plates, lube mods for better reliability, etc. Try to get a vette unit or at least one out of a TPI car (IROC or GTA preferred) as it will already have stiffer servo springs and the big 2/4 servo which gives you nice crisp shifts but wont rattle your teeth at light throttle. One plus of the vette unit is that it will shift into OD at WOT where as some of the F body boxes will and some wont.

Pick up a "Beast" sun shell as the stock sun shell is a failure prone factory part and the beast part is cheaper than the updated GM 4L60E part if you shop around ebay.

If youre going to build the unit yourself then pick up an ATSG manual (ebay for ~$12) as well as a rebuild video of some type. Both those will help quite a bit if youre not familiar with building the unit.

If I can help just shoot me a PM or email as there are a few things you can do to help reliability that arent mentioned in the ATSG manual.

bnoon
02-02-2005, 06:33 AM
Yeah, I've got a Vette servo setup ready to go since it's a rather popular thirdgen mod and I've also got a related line pressure modification/fix how to somewhere around here for better second gear holding power (quite a ratio change shifting to second). Where do I pick up a "Beast" sun shell though?

Searching for net for that and ATSG manual...

bnoon
02-02-2005, 07:09 AM
Nevermind, found them both. :yeah:

myclone
02-02-2005, 07:09 AM
Where do I pick up a "Beast" sun shell though?

Searching for net for that and ATSG manual...

Ive seen the beast shell for sale on ebay by doing a search under "car and truck parts" then going to "transmissions" then typing in "700R4" and doing a search. You could prolly just do a search for "beast" in the trans section since there are usually several pages of 700 parts if you dont want to wade through all of the other pages. If memory serves me correct is seems that at times I would find several beast shells for sale while others there werent any so it may take scouring ebay for a few days to find one if there arent any listed on the day you look. There are usually several auctions for the ATSG manual though but be sure to get the one that covers the year trans youre working on since there are two different ATSG manuals available for the 700 (83-87 and 87-up).

bnoon
02-02-2005, 07:24 AM
By the way, would you know the part number for the new GM 5 gear planet?

myclone
02-02-2005, 07:47 AM
Front planet: 24218063 ($127.40 last I time I bought one)
Rear planet: 24218069 ($257 last time)

myclone
02-02-2005, 08:04 AM
Here are some more part #s you should check into for greater reliability.

8685044 One piece apply plate for the 3-4 stack (replaces failure prone 3 piece. $6)

8585043 A little heavier duty apply ring than whats normally found in a 700 ($14).

24200290 3-4 apply piston with molded rubber seal. Replaces piston that has seperate seal which can blow off under high press/hi po driving ($27).

24205272 Forward piston with molded rubber seal. Ditto on the reason for upgrade as above piston ($27)

24210961 High torque input sprag assembly package. Used on H2s and includes sprag, overrun clutch hub, retainer, inner/outer races, snap ring, and sun gear ($168).

24217328 Torrington roller bearing coversion for the reaction shaft to shell. Replaces a bronze thrust washer that can fail when driving "spiritedly" ($9)

8642191 Another torrington roller bearing replacement for thrust washer for the front planet and reaction carrier shaft ($4).

The "kit" for clutches, steels, seals, and gaskets for hi po use I like is from Transtar and is about $285.00 which includes blue plate clutches, Kolen steels, and a High Energy 2/4 band (wider 2/4 band). Part # K6100HP.

BTW, if you replace the trust washers with the torrington bearings then total thrust end play is CRITICAL. Too loose and you beat the torringtons to death and too tight you will end up with negative thrust clearance which will shatter the bearings and pieces of the bearings will ruine other expensive parts as well. With the bronze thrust washers they just get ground up into fine dust if the thrust clearance is less than optimum with no harm really done. I set my total thrust clearance at .005" but Im also VERY aware of fluid temps when racing so as not to over heat the alum pump and close up the thrust clearance. You can set your clearance to around .010" if you want and you should be ok if you dont run a trans fluid temp gauge. If you do install a temp gauge, which I highly recommend, plumb it into the "fluid out" line (the line carrying hot fluid to the cooler) as close to the trans as possible so you will get a more accurate reading of the internal temps of the trans. Plumbing a temp sending unit into the pan or anywhere else will only give you the temps of the fluid at that point not the heat its picking up where the stresses are highest in the gear train of the trans.

If you dont mind the cost use Red Line High Temp trans fluid but if the $100 a case cost of it is too much to swallow for a trans that sees limited track use then just use Dextron III with the biggest cooler you can fit in front of the radiator. The bigger cooler the better. Keep temps as low as possible and if you are racing and the temps get above 270deg let the trans cool some before going back out. At around 270 regular Dextron III is starting to break down and death to the trans cometh shortly. If you make a pass at the drag strip and the temps temporarily spike to 270 or slightly above but come back down quickly youre ok but spend any length of time running at or above that temp will kill the fluid (and the trans) after a while.

HTH

bnoon
02-02-2005, 08:06 AM
Thanks man! http://www.gmpartsdirect.com (http://www.gmpartsdirect.com/) has them for $121.46 and $245.52 shipped, so your prices are still pretty close!

I'm having trouble finding the 10 vane pump you mentioned though. Who did you get that part through?

Also, a question for this portion "Reverse input drum MUST be flat where the 2-4 band applies." I'm having trouble visualizing... Will this become more apparent when I'm looking at that portion of the rebuild? Is there anything you can do to expound on the description?

bnoon
02-02-2005, 08:08 AM
Here are some more part #s you should check into for greater reliability.

8685044 One piece apply plate for the 3-4 stack (replaces failure prone 3 piece. $6)

8585043 A little heavier duty apply ring than whats normally found in a 700 ($14).

24200290 3-4 apply piston with molded rubber seal. Replaces piston that has seperate seal which can blow off under high press/hi po driving ($27).

24205272 Forward piston with molded rubber seal. Ditto on the reason for upgrade as above piston ($27)

24210961 High torque input sprag assembly package. Used on H2s and includes sprag, overrun clutch hub, retainer, inner/outer races, snap ring, and sun gear ($168).

24217328 Torrington roller bearing coversion for the reaction shaft to shell. Replaces a bronze thrust washer that can fail when driving "spiritedly" ($9)

8642191 Another torrington roller bearing replacement for thrust washer for the front planet and reaction carrier shaft ($4).

The "kit" for clutches, steels, seals, and gaskets for hi po use I like is from Transtar and is about $285.00 which includes blue plate clutches, Kolen steels, and a High Energy 2/4 band (wider 2/4 band). Part # K6100HP

HTH

You rock!!!:firefire:

myclone
02-02-2005, 08:43 AM
Thanks man! http://www.gmpartsdirect.com (http://www.gmpartsdirect.com/) has them for $121.46 and $245.52 shipped, so your prices are still pretty close!

My prices were from the local dealer parts dept so gmpartsdirect is prolly cheaper but....be aware of possible high shipping costs. Thats where gmpartsdirect seem to make their money (BTDT).


I'm having trouble finding the 10 vane pump you mentioned though. Who did you get that part through?

If you have a later 700 then it will have a 10 vane pump already. The earliest years had an inadequate 7 vane pump which you do NOT want (low volume for hi po applications). 13 vane pumps are aftermarket which I personally avoid after other ppl have had failures of the rotor in those when using high line pressures.


Also, a question for this portion "Reverse input drum MUST be flat where the 2-4 band applies." I'm having trouble visualizing... Will this become more apparent when I'm looking at that portion of the rebuild? Is there anything you can do to expound on the description?

Its simple once you see it but tough to explain. The ATSG manuals have a drawing of this and what to check for so it should be pretty clear when you see it. Basically what happens with some used rev input drums is the band wears the flat surface it applies to a "dish" shape and when you put in a new band only the higher outter edges of the rev input drum come in contact with the very outter edges of the new band. This doesnt provide enough contact area for the band to hold so it slips causing the outter edges of the band to burn and a mushy 2nd gear. BTW, once frictions are "burnt" their coefficient of friction goes WAY down so the problem only compounds itself and no amount of repairs can save the frictions and they must be replaced. FWIW, Ive only found a few rev input drums that were worn in the band area (stupid high mile units) so IMO its not a common problem but one that if over looked can be a PIA since an otherwise good trans will slip if its not noticed.

The biggest issue Ive found on the rev input drum is that the "lugs" on top of the drum get flaired outward from abuse which causes them to rub the inside of the case and this fills the trans full of alum particles which causes accelerated wear on everything. Check BOTH the lugs and the band surface on the rev input drum for straightness and look on the inside of the case for evidence of the lugs on the drum rubbing the inside of the case as well. The ATSG manual describes all that with text and diagrams but if you still have trouble lemme know and later on I can take a pic of what Im talking about and post it.

myclone
02-02-2005, 09:17 AM
Some things I should mention before you spend a bunch of hard earned money as well as your time on if this is your first trans build... While 700s are fairly easy to build once youve done it they are complicated units compared to a TH350, 400, or power glide so be VERY aware of the parts when you tear the unit down. In GMs infinite wisidom they mixed pieces togeather from the factory that if mismatched with non compatible parts on reassembly will yeild a trans that wont work or has a mind of its own as to how hard it shifts and when.

There are several versions of input shaft/drums in the late units as well as servo and valve body configurations and the ATSG manual covers most but not all of them. That being said go SLOWLY and identify what you have when you take the trans apart. Also, I cant stress enough to start with a factory hi po unit rather than trying to take say a TBI 305 unit and trying to make it shift hard. It can be done but I dont recommend it for someones "first time" at building a trans but once youve rebuilt a few then you can start getting creative.

Lemme put it this way... I started messing with 700s after scattering the first one in my syclone a few years ago and I refused to pay $3500+ for a trans that "we wont guarentee in a syclone/typhoon". My first 700 I built lasted a week in a TBI 350 truck and the second lasted a few months in the same truck cause I thought the 700 was like a SBC and I could throw it togeather with my eyes closed. I quickly learned I was mistaken and to follow the ATSG manual to the letter, pay attention to what parts I had when I tore the trans down, and to double check everything when reassembling. So far Ive built a couple of dozen 700s for friends and my own projects and all has went well since I started paying attention.

Last thing.. The above paragraph doesnt count the 13 times Ive broken the 700 in my syclone (its broke now) though its not clutches or line pressure thats the issue now its that Im breaking hard parts like input shafts, GM 5 gear planets, and output shafts (all those were cryo treated BTW). That being said just remember that no matter what you do to a 700 if you put a LOT of torque through it with traction or drive insanely its going to break sooner or later. Not if but when ....I promise.

For the record Im going to R&R the syclone trans for the 14th time just for the hell of it but when it breaks again the needed parts are in a box on my work bench for a 4L80E upgrade. Then I can get back to making HP and beating up "fast" cars with a truck not spending my time fixing the trans :naughty: .

bnoon
02-02-2005, 10:45 AM
My prices were from the local dealer parts dept so gmpartsdirect is prolly cheaper but....be aware of possible high shipping costs. Thats where gmpartsdirect seem to make their money (BTDT).


Those were the shipped prices, so we're cool!



If you have a later 700 then it will have a 10 vane pump already. The earliest years had an inadequate 7 vane pump which you do NOT want (low volume for hi po applications). 13 vane pumps are aftermarket which I personally avoid after other ppl have had failures of the rotor in those when using high line pressures.

Cool. Thanks for the info!




Its simple once you see it but tough to explain. The ATSG manuals have a drawing of this and what to check for so it should be pretty clear when you see it. Basically what happens with some used rev input drums is the band wears the flat surface it applies to a "dish" shape and when you put in a new band only the higher outter edges of the rev input drum come in contact with the very outter edges of the new band. This doesnt provide enough contact area for the band to hold so it slips causing the outter edges of the band to burn and a mushy 2nd gear. BTW, once frictions are "burnt" their coefficient of friction goes WAY down so the problem only compounds itself and no amount of repairs can save the frictions and they must be replaced. FWIW, Ive only found a few rev input drums that were worn in the band area (stupid high mile units) so IMO its not a common problem but one that if over looked can be a PIA since an otherwise good trans will slip if its not noticed.

The biggest issue Ive found on the rev input drum is that the "lugs" on top of the drum get flaired outward from abuse which causes them to rub the inside of the case and this fills the trans full of alum particles which causes accelerated wear on everything. Check BOTH the lugs and the band surface on the rev input drum for straightness and look on the inside of the case for evidence of the lugs on the drum rubbing the inside of the case as well. The ATSG manual describes all that with text and diagrams but if you still have trouble lemme know and later on I can take a pic of what Im talking about and post it.

Again, excellent info! You explained it b-e-a-utifully!!! I shouldn't have to much of a problem with the reverse input drum since I now have two shots at getting a good one (just found another donor trans that a friend has in his garage when I was calling everyone I know looking for local parts). I'll be sure to check it out before assembly.

bnoon
02-02-2005, 10:54 AM
Don't worry, I'll get ahold of you if I have troubles! I usually take things apart in an exploded diagram type of way to keep parts organized and in the right order. I shouldn't have to much trouble (knock on wood) since I have built other transmissions before, just not a 700. The GM TH 350/400's are easy, even when compared to a Ford C4/6, let alone a Ford AODE trans like in a friend's older Mustang GT. Can you compare it to any of those, or is it complicated further still?

FYI, both of the 700R4's that I have are 305 TPI units. Do you know if the 305 TPI's 700 shares it's guts with the TBI 305 or TPI 350??? Please say 350, please say 350...

myclone
02-02-2005, 11:03 AM
Don't worry, I'll get ahold of you if I have troubles! I usually take things apart in an exploded diagram type of way to keep parts organized and in the right order. I shouldn't have to much trouble (knock on wood) since I have built other transmissions before, just not a 700. The GM TH 350/400's are easy, even when compared to a Ford C4/6, let alone a Ford AODE trans like in a friend's older Mustang GT. Can you compare it to any of those, or is it complicated further still?

From what I gather the 700 would be an equivelant to the ford OD but Ive yet to tear into the OD unit that ford has. Just what Ive heard from other ppl.


FYI, both of the 700R4's that I have are 305 TPI units. Do you know if the 305 TPI's 700 shares it's guts with the TBI 305 or TPI 350??? Please say 350, please say 350...

V8s share a lot of the same parts and clutch count (V6s have fewer clutches) but the TBI units usually have quite a bit softer shift quality than the TPI units. Off the top of my head if the units you have were from TPI cars then you should be ok. Put the vette 2/4 servo in along with a .500 boost valve and grind the land off the pressure regulator valve and you shouldnt have to get into searching out different servo springs and other misc parts to firm up the shifts (BTW, the grinding mod is shown/explained in the ATSG manual).

Oh, couple more things..

Once you get the trans torn down remove the check ball and its retainer from the end of the input shaft (called the turbine shaft). Throw away the check ball and put JUST the retainer back in. This=firmer torque converter clutch apply less slippage which helps with heat and is mentioned in the ATSG manual.

Once you get your ATSG manual look at the 2-4 servo line up diagram. There is an exploded diagram of the line up and in a dotted box there is a spring that is labelled "some applications". If you dont have this extra spring install one to firm up 2nd gear shifts some. You can use a spring out of the 1-2 servo in the other trans you said you have and just put this spring inside the the existing spring and reassemble (putting one inside the other is the same as putting in a single stiffer spring...cheap/free shift kit so to speak). Firmer 1-2 shift than just the vette servo alone but not brutal.

You can firm up the 1-2 shift even more by removing the 1-2 accumulator and flipping the spring and piston positions. This takes the spring out of the circuit so now there isnt any "give" when 2nd hits. This=VERY firm 2nd apply and you may want to wait to do this until youve decided that 2nd gear apply isnt firm enough for your liking. You can do this mod later since it doesnt require removing the valve body just the pan and the three bolts out of the 1-2 servo cover.

FWIW, the servo springs Im talking about act like water hammer arrestors in your house. Basically when fluid is applied to a clutch its also applied to the servo piston at the same time and the spring compresses slightly. This offers a "cushioning" affect so when you install multiple springs or a single stiff springs you are taking away some of the servos ability to cushion the shift engagement hence a firmer shift. Flipping the 1-2 servo and spring completely eliminates any cushion since the servo is now resting on the valve body seperator plate with no spring under it so it has no "give" what so ever. Translation=really firm/hard 1-2 shift.

myclone
02-02-2005, 11:27 AM
Oops, double post.

bnoon
02-03-2005, 07:51 AM
O.K., I just found out that my spare trans has a cracked 4 planet carrier... no problem, right? Well, there's a small chunk missing and I don't want to use this trans if I don't have to... Everything looks a bit more worn than I would like, even for a rebuilder core... everything feels tainted. So I went to ask about the second trans that's in a friend's garage... 4x4 output shaft and tail housing... I remembered the tailshaft, but forgot about what a pain that output shaft is! ARRRG! No biggie if I wanted to grab the longer output shaft from the "tainted" trans, but I'd rather have new. The other tail housing is fine as long as I use a new seal, so...

Do you happen to know the part number for the new correct length output shaft? Couldn't find one on the bay or through GMPartsdirect (yet)...

myclone
02-03-2005, 10:33 AM
Do you happen to know the part number for the new correct length output shaft? Couldn't find one on the bay or through GMPartsdirect (yet)...

Sorry, I dont have the part # handy for a 2wd output shaft but the used 2wd shaft should be fine. As long as the splines arent worn heavily and the machined bearing surfaces are in good shape a new one would be extra money spent for no real reason IMO (other than piece of mind). If youre never going to use slicks then youll break the internals long before you break an output shaft. Yes, Ive broken one but then again Im AWD and launching with 15psi of boost which puts WAY more stress on it than you would be able to being RWD and on street tires/drag radials.

BTW, 2wd and 4wd output shafts are 100% interchangable so other than tearing the trans completely apart to get to the snap ring its a R&R type deal. Iirc the only thing youll need is a tail housing for an F body, which you should already have, since the torque arm mounts to it.

bnoon
02-03-2005, 11:51 AM
BTW, 2wd and 4wd output shafts are 100% interchangable so other than tearing the trans completely apart to get to the snap ring its a R&R type deal. Iirc the only thing youll need is a tail housing for an F body, which you should already have, since the torque arm mounts to it.

Yeah, I know that part. The trans itself is from an '86 TA just like mine. The part I forgot about is that it was in an S-15 Jimmy 4x4 project truck after it came out of the TA.

There are some marks on the output shaft of the other trans, which is why I'm looking for a new/used one in good shape now. If it were easier to swap out, I would rebuild the trans and then put mine from my car in it... but since it's a bit deep into the trans work to replace it, it hardly makes sense to try to do all of the work before hand and leave the output shaft until last. Two spare trannies, one in the car, and I can't fully rebuild one of them without taking my car off of the road.
:banghead: