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700R4 low pressures?

27K views 136 replies 9 participants last post by  '49 Ford Coupe 
#1 · (Edited)
Hi folks, I am getting ready to go into my 700R4 to do some more mods and correct some errors I made in last winter's build. I did before work pressure tests this morning and got some troubling results. Minimum TV, in P, N, D, 3 @ 1,000rpm, pressure is 90psi which is fine. But then in reverse, pressure @ 1,000 is only 110. In manual 1st and 2nd, pressure @ 1,000 is still just 90 psi. Full TV, pressure in P is 105. N is 110. D is 95. Man 3rd is 100. Man 1st and 2nd is 100. When I raise rpm to 2,000, pressures @ full TV are P & N- 220, R-210, D 190, 3-200, 1&2-210. Gauge is steady(no wiggly needle). In R, D and 3, when I rev the motor with the TV locked full open, pressure jumps to 240 before falling back off to the readings listed above. I wonder if that might be the pressure relief valve opening. I would like that to hold til 300psi if possible.

The unit has a .296 rev boost valve and the .500 TV boost valve with a high rate regulator valve spring. I have dual springs on the line bias valve and a new 10 vane pump. I expected much better readings. My ignorance is that I put the unit together and drove it most of the summer without pressure testing. Won't make that mistake again. To make things worse, the TCC never worked since the build and I know I got it hot. I know that there are probably several things that could cause this kind of behavior. Does anyone have any thoughts? What jumps to the front of your mind? Sealing ring(s)? Damaged pump? Gasket blown? I plan to go into the unit first thing in the morning and have the weekend to get it back together. I have a full gasket set, new sealing rings, and some other goodies to put in it. If I need other parts, I will need to run to Portland tomorrow to get them. Up side is that it is coming winter and I don't drive the car in anything but sunshine. Worst case is I find something wasted that I can't get tomorrow, I put it back together best I can, limp it home and go back in later better prepared. Moral of this story is pressure test before you drive it. Damn!

I am very thankful for any help. Go ahead and chew my butt. I've earned it.
 
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#82 ·
Wow Hogg. That's alot of information. Thanks for adding the other vehicles to the list of those that have the heavy duty planets and reaction shaft.

I put together a little price list today and for not much money I can go ahead and replace all of the bushings and the reaction shaft. I know it's one more time into the unit but aside from a few quarts of fluid and a pump gasket, I'm, not out anything. I'm getting to where I can practically D&R this thing in my sleep. I'm going to take extra care this time to be sure that everything is perfect so I don't have to mess with it again anytime soon. I guess I said that last time but I wasn't really expecting to have so many issues. I feel very good about the overall build now. I just need to address the end play and I really want to get rid of the bi metal thrust washer.

On this last teardown, I didn't expect to find so much damage, all caused by the 3-4 clutch failure. I am very confident that with the pressures and cooling system I have with things set up right, there will be no more issues with the 3-4 clutches. While I corrected pretty much all of the issues caused by the 3-4 failure, I didn't replace the bi-metal thrust washer that also got torn up some. The wear of the washer added alot of end play. With the upgrades I'll be doing now, I'll be able to set up end play to the correct spec and have it stay there.

One thing I need to get is a bushing driver set for this trans. Pro Built has a set just for this unit for $179 which is a great price. I may just go with Snap On though since I can put it on the truck account and pay for it in installments with no interest. I'll get the bushings here and measure them to know what size drivers I need.
 
#83 ·
Kind of makes me want to shell out some cash for a stand alone 4l60e HD tranny. A toggle shifter would be cool to.
So what do you think if any performance transmission builders out there who build them for a living saw what's on these few pages, they might have a cow....Then again they have probable moved on to 4l80e,s an such.
 
#84 ·
I think the real pros already know this stuff. They don't likely care whether we know it or not. Their big advantage is that through experience, they know how to get it right the first time. Guys like Crosley just watch us and wait for us to ask the right questions. They have the answers.

It's starting to wear on me that this will be the 3rd time I've been into this unit. I'm not even going to tell my wife that I plan to spend more money and time going through this trans one more time. She was on me last time to just take it to a pro and have it done. On the other hand, it took the guys who built it for me back in 2000 three times as well. My solice comes first from knowing that when I get it all done, I will know the unit inside and out. It will no longer be a part of my car, every other part of which I built with my own hands, that is a mystery to me. Second, from knowing that it will be far superior to what most any trans shop would have done for me.

Parts like the Smart Tech input housing, which as part of a properly built transmission produces a near indestructible 3-4 clutch pack, most builders wouldn't have used because of the high cost. For me, it just makes sense because the 3-4 clutch is such a problem. This clutch is the reason it took three tries to get the trans to hold up last time. The 3-4 clutch setup I have now is heads and shoulders above what was in there before.

As far as the 4L80E goes, except for big block or supercharged applications running 1000+ hp or tons of torque, I feel like it's just too heavy to be practical in anything lighter than a truck or large sedan. As long as we keep power in a coupe or mid size under 1000hp and don't run slicks, I think the 700R4 or 2004R will always be great options. Improvements continue to be made to the 700R4 at least. I don't know about the 2004R so I can't say, but better, stronger parts just keep showing up for the 700s like the new super strong input shafts from Sonnax and others. These are more pricey parts but make the trans even beefier.
 
#85 ·
I hope this doesn't cause any issues but there is a thread going on thirdgen.org concerning a 700R4 build and a member posted a link to a good pictorial of a rebuild by someone who obviously knows what he's doing. He uses all of the factory tools to go through the unit. The thread on TGO is in the Transmission and Drivetrain forum and started by Ozz1967. If I was better at the computer I would just post a link but sorry. I only posted about this thread because this run through is pretty good. Wish there was more detail on installing lip seals. That is one part of the job that is really tricky to get right.
 
#86 ·
For the lip seals I used that round green colored thing, can't remember what its called. After I got the hang of it it worked pretty good. Just bend it an turn it at the same time. Besides the 700 that's in the car I have another one (1990 yr. mod.) bought it off of Craigslist for 50.00. The guy was having problems with it so the trans. shop put in a rebuilt valve body, then he said he drove it another 2000 miles or so an it failed again, it had burned up the band an the 3-4 clutches were burned up to, that's what I found when I took it apart. I was thinking that I got a good valve body at the least. Anyhow I've got it hanging around just in case. It would be easier for you if you have an extra 700 that was half way built. You must have access to a lift, that makes it a lot easier to put them out. I had to put a few 2x6's under my biggest jack stands just to be able to slid the trans under the car, then I had to get it onto my roll under jack an then get the torque converter on which must weight 60 lbs. onto the trans while laying on the garage floor . Not easy at all!!!! An no help either.
 
#88 ·
I think it's called seal buddy or some dumb thing. I used it too and it works okay with a little practice and lots of lube. I paid good money for the factory tools to install the forward and overrun pistons. Couldn't use either of them because of the input housing reinforcement ring.

I built my car on jack stands back in 99. Spent 4 months between the creeper and bent over the front end. Since then, I have always worked on lifts and got spoiled. When I did the trans build last winter, I had the car on stands for the R&I portion of the job. It took twice as long and man was I tired from working so long in that position. For the weekend in and out trans work I've done since then, I'm using a lift at the shop. Warm, well lighted work area, all my tools right there and no working on my back. I am spoiled.
 
#87 ·
Gm lists the 4l60e as weighing up to 194lbs wet, and the 4l80e at 255lbs.

I dont see any 4l60e/65e/70e 700r4 being reliable in big power applications or trucks. But I do see a lot of issues with these transmissions being related to the builder. I paid big bucks for s 60e build locally and had better luck with stock 60e's.


Ive seen pictures of 200r4 and 700r4 parts side by side, and a lot of teh 700r4 parts are substantially larger that the 200r4.

The 200r4 has the best all around gear ratios IMO. I just wish the 200r4 had the 4l80e strength and shift feel. It has a 1st gear ratio that splits the 4l80e (2.48)and 700r4's(3.06) 1st gears at 2.74:1 and also has the deep 0.67:1 OD ratio like the new 6 speed autos have.

Having quality trans builder is worth their weight in gold.

peace
Hog
 
#89 ·
I harassed Crosley some more over the weekend. We talked about his modification converting the reverse input drum/pump thrust washer to a torrington bearing. His method is to use a TH350 pump torrington in place of the washer and locate it using a longer(2004R) bushing at the front of the drum. He told me that it may be necessary to machine the stator support for clearance. PATC offers a modified drum, machined to accept a torrington bearing in place of the washer. Assuming that they have machined the drum for correct end clearance with the bearing, this may be the easier way to go. They want $205 for the part which is a chunk of change but if it is a drop in replacement, it may be worth it to avoid issues with clearance.

At this point, I'm thinking that I will go through and replace all bushings and install the late style reaction shaft with torrington bearing. Then, I'll work on collecting the other parts to do the rest of the work in another year or two. I never had any issue with that washer behind the pump so I think it will be fine for now. Eventually though, as part of preparing the unit for higher rpm stability and more power capacity, I will replace all of the thrust washers with bearings. I may also replace the input shaft with a new super duty piece. Sonnax for one, makes a high strength shaft for the 700R4.
 
#90 ·
lWe have more older Chevrolet trucks running around with th350 in them than their original 700 r4 trannys. Some got so tired of rebuilding they just put in the th350 out of frustration . Even when I asked the tranny builder why, he just said they were used to hard compared to the cars. That is one of the reasons I chose the 200 4r. I've had the pan off mine four times now, and it still looks good inside. No junk in the pan at all. I can understand why the bigger heavier trannys with bigger horse powder, but the 200 4r works good in my nova with the healthy 350.
 
#91 ·
My first choose was going to be a 200r4, I even bought a torque converter for a 200r4 but when I got a 4l60e for free I was going to use it until I found out how much a stand alone controller was. I did some research an found out I could use a lot of the parts from the 4l60e in a 700r4. I bought a used 700 for 75.00, not knowing at the time what the green tag that said remanufactured by Hydromantic meant. At the same time I had a want add on Craigslist for a used 700r4 an bought another 700 for 50.00. The guy I bought it from said He had just replaced the valve body with a rebuilt one, but it didn't fix his problems. I figured a rebuilt valve body was worth the 50.00. So I ended up using a 700. I had the torque converter switch over to fit a 700r4. Getting rid of the TH350 an putting in 700r4 has been a big improvement in the rpm's at 70mph. I was turning around 3000 at 70 now its turning 2200 in OD.
 
#92 ·
From a design standpoint, sometimes a Torrington style "lazy susan" bearing is not a good idea versus the steel-backed bronze washer.

In a torrington bearing the rollers are the same diameter at both ends, the "outside" end of the individual roller wants to move at a different speed than the "inside end" just like when you make a turn with your car. Just because something says HD, it doesn't necessarily mean "High Speed." What happens is the rollers will start to skid and generate heat, eventually the thrustbearing will fail. We service an industrial gearbox that has 2 different models. The early model uses a thrust washer (steel backed bronze), the later one uses a Torrington bearing. The Torrington bearing is a frequent failure point in the exact same application

The right answer for some applications is a tapered roller "lazy susan" bearing. Timken makes one called a TTCL. However these are custom bearings and not cheap.

If the Torrington bearing is holding up; great, keep on using it, but its not always the answer. We've gone to using custom steel-backed bronze thrust washers instead of plain steel ones in our competition 4spd gearboxes. When we get them back for inspection, the washers are almost always still serviceable, however they're replaced along with new sealed ball bearings. We looked at Torringtons, but our RPM and loads can be pretty severe.
 
#93 · (Edited)
Wow, thanks to Hogg and dogwater for the additional information.looks like I have my target, just have to find one or more and get to building. I'm heading over to thirdgen to see about the thread asedoc posted. I'll put up a link when I find it.

Also thanks to autogear for the bearing vs washer tech. I talked to my dad about the issue and he had similar thoughts. He is a mechanical engineer with a PE and about 50yrs experience so I trust what he has to say. His thought were that less moving parts as long as well lubricated(cooled) was a better and even had less friction as it was riding the hydraulic wedge and not pushing rollers and a cage around

Picked up new(er) tranmission, what can you guys tell me about it? - Third Generation F-Body Message Boards
Is this the thread? It didn't have pix as you suggested.
 
#94 ·
Im sorry. I got mixed up on what thread was which. The pictorial I was referring to is linked by vettoz in the thread, by Ozz that you just linked to. It's the 4 page link in post #23.

I am also very intrigued by the discussion on thrust washers vs. Torrington bearings. I assumed that because GM made the switch in the later years as they worked to increase torque capacity in the 4L60, that the Torringtons must be better. One supplier offers the late reaction shaft(takes the Torrington instead of a washer) as an upgrade. I have always known that the needles in a Torrington don't really roll evenly. It's obvious that a non tapered needle isn't going to roll in a circle. Still, when you look at the 700R4/4L60, you see where they have used Torrington bearings for years in high stress locations and these bearings never fail.

I realize as I think about it, even after 25K miles of hard use, the steel backed bronze washer that came out of the unit last winter was still in pretty good shape. I replaced it of course as part of the rebuild. The new one that's in there now was torn up when the 3-4 clutches failed after the rebuild. Maybe what I need is just a new bronze thrust washer. They do offer one that is PTFE coated to ease break in.

Today was Christmas at work and along with flagging a record 2 weeks, I got a fat bonus. So now I'll think about how to proceed on this and make my move on Monday.
 
#95 ·
I'm thinking their is varying pressure on the torringtons thru out the transmission. I'm sure GM thought about this. I'm going a little off subject here, does GM in fact design an build their auto transmissions?
If there was a spot in the trans that had consistent pressure (pushing against each other) then I would of hoped that they used a tapered roller bearing. But when you think about it, its turning force, that where the pressure is.
 
#96 · (Edited)
Different phases(gear) of operation apply different forces on the parts of the trans. I know that with a trans brake it applies force in one direction the when released that force is pushed to other bushings/bearings. I'm not sure there is one that sees the same force In each phase of operation.

There is a plastic washer in the 2004r under the sprag in one of the planetaries that is reccomended to be replaced with a bearing no matter as gm updated to the bearing in later years. I think this is heat related failure as the metal torrington will take way more heat than a plastic piece will. And where it is situated, once the sprag and planetary are heated up they just don't get cooled resulting in a melted washer.



700R4 - 4L60 Build Up Inside [Forums - C4 Technical] - CorvetteGuruForum.com
700R4-4L60 Build Up Part 2 [Forums - C4 Technical] - CorvetteGuruForum.com
700R4-4L60 Build Up Part 3 [Forums - C4 Technical] - CorvetteGuruForum.com
700R4-4L60 Build Up Part 4 [Forums - C4 Technical] - CorvetteGuruForum.com
700R4-4L60 Build Up Part 5 [Forums - C4 Technical] - CorvetteGuruForum.com
 
#97 ·
Thanks Texas T for linking the thread I was referring to before. That is a pretty decent run through of the rebuild process.

As far as thrust pressure is concerned, anytime helical cut gears are used, some of the rotational force applied to a gear set is going to be converted into end force. When rotational force changes direction, as in accel/decel, the end force is also going to change direction. This is why correct end play setting is so important. Excessive end play will lead to hammering of parts when direction of force changes. As said before, the Torrington bearing is not perfect since the needles don't roll smoothly in a circle. But, the Torrington works. It apparently works quite well in an automatic transmission, since they seem to last a lifetime. Of course lubrication and cooling have to be good to ensure a long life, as with all the internals of the unit.

I ordered my new reaction shaft with Torrington bearings today, along with a new band since mine has a small chunk of friction broken off from my mis handling. Ive since learned the correct method for installing the band, so no further damage should occur. I also ordered new bushings and when they arrive, I'll measure them and get the correct size drivers from Snap On.
 
#98 ·
Snap-on bushing drivers.... One thing I did was when I could get one out without mucking it up I'd use the old one to install the new one. I didn't have a press either but I do have a big *** bench vice. Also used a 8 in. long 1/2 bolt that I had to cut more threads on it. An a boat load of different size 1/2 in. washers. Then I found out that you need something to back up the washer because the washer will **** inside the bore thus pushing the bushing in crooked. It was a giant pain in the ***, so what ever bushing drivers you can get,do it.
 
#99 ·
I am a Snap On victim, over 20 years time, enough to buy a nice home. I find that in my profession, using my tools every day to make my living, they are worth the money. But, the reason I'm going with Snappy on the drivers is simple economics. While I can buy a set of drivers for alot less from Pro Built Automatics, my truck account with Snappy will let me buy just the ones I need and pay for them over a few months time with no finance charge. Pretty good deal. Plus, if I foul one up, I get a brand new one to replace it for free, no questions asked.

I'm already thinking maybe I need to get another set of bushings. The Corvette Guru installed two bushings instead of one at one end of the front sun gear. I'm going to review his buildup for the details. I haven't heard anything from Crosley on this, Crosley is my transmission guru, but it sounds like it could be a good idea. At $18, the bushings are a cheap investment.
 
#100 ·
Well I stand corrected. I just looked through every post of the Corvette Guru's 700R4 build and didn't see anything about the sun gear bushings. Guess I saw that somewhere else. I did order the double wide rear sun gear bushing along with the set, so I'm covered there.
 
#101 ·
I see nothing wrong with purchasing quality tools. I can't due to budgetary contstaints but I can appreciate using what I has(disregard the snappy stuff in my pix I'm not sure where they came from haha).

I've not seen the double sungear bushing though I will be putting forth a google search on the subject along with a through reread of the corvette guru threads on 4l60e assembly. Mine is a 94. I have the original and a used one that stopped shifting.out of first. As soon as the 2004r is in the car and working out comes the 4l60e and appart it will come.

Great info in this thread. Keep up he good work and Merry Christmas.
 
#102 ·
There was one bushing that I had problems with not wanting to fit on the output shaft and I don't remember which one it was for sure but it was to tight. I'm thinking it was on the 4l60e reaction shaft, I remember it was a 4l60e part an I was using 700r4 bushings. You might run into this also maybe. What I did was by using valve grinding compound, the stuff that's in a squeeze tube, I put some on the output shaft an some on the ID of the bushing, mounted it on the bench vice an slowly pushed it on an turning at the the same time. It took some time but I got it to fit. Then cleaned an washed everything. I do remember that I checked the p/n for each bushing an they we we the same. Another thing is to smear some red locktite on the OD of all the bushing before installing, an don't cover any oiling holes with the bushing. And I did them one at a time so not to mix anything up, cause all my info. didn't say which bushing goes where only that a bushing needs to be there. Some bushing have groves in them some don't , just replace like bushings with like bushings. FYI
 
#103 ·
Thanks dogwater for the heads up on the bushings. I have had trouble before with bushings running tight after install. As far as I know it's because the bushing gets compressed or deformed from installation. That's why the correct bushing driver fits snug inside the bushing to prevent deformation. In the pictorial that Texas T linked above, the guy suggests locktight green sleeve retainer for the bushings. I have some leftover from the input shaft install and may get more. Now that I think about it, the one bushing I tried to drive out from my extra rear Sun gear didn't want to break loose. The locktight may have been the cause of that. I may apply some gentle heat and see if that helps. Heat is usually the key to releasing locktight.

Turns out that as far as the double front Sun gear bushing mod goes, I was confusing the TH350 and 700R4 with each other. I remembered that mod from looking up a TH350 build. I will install the double wide rear Sun gear bushing. This whole bushing replacement process could all turn out to be pretty easy. The front pump and stator are newly rebuilt with the upgraded bushings already installed. The reverse input housing has new bushings, the reaction shaft should also come with new bushings. The only bushings I'll have to deal with are the sun gears, tail shaft, and rear case. Hopefully. Well see when I get there.
 
#104 ·
New pieces just showed up. The reaction shaft looks great. It is a tight fit to the ring gear so I'll warm the gear up for assembly. That should help. I see the reaction shaft has 5 reliefs machined into the front edge that need to align with the lube holes in the gear. The new shaft came with the late style wide aluminum bushings installed. That leaves just the sun gears, rear case and tail shaft bushings to install. I'll measure the bushings and match the sizes to drivers from the Snap On catalog. Getting closer to being ready.
 
#105 ·
I've decided to scrap the Snap On bushing driver idea and just go with a set of specific drivers for the 700R4. Pro built no longer offers them but Dana gave me some leads to find a set and I located one at Streetside Tools. They want $179 for it. This will give the all the correct sizes to do the complete trans and will make future overhauls easier.

I also found an interesting part upgrade. Crosley had mentioned in another thread using a different front bushing in the reverse input drum and a torrington bearing in place of the front pump thrust washer. I found a set from Greater Dimensions Engineering that includes a modified bushing and torrington bearing for this purpose. The set was only $19 so I ordered it. I was going to hold off on that mod for now but I may as well do it since I'll have the parts.

With the mods I'll be doing, the only thrust washer left in the trans will be between the low/rev roller clutch inner race and the sun shell. The rest will be replaced with torrington bearings.
 
#106 ·
So.... now that I'm pretty much ready to go on the final foray into this trans(for some years I hope), I was thinking, why not go all the way and just get the smart shell too while I'm at it. It's only another $90 +shipping. I'll make most of that on a quick 1hr side job this weekend. The smart shell with the re-machined low/rev roller clutch race that goes with it, will eliminate the last thrust washer from the trans and it's also lighter than the Beast shell, while still being plenty strong. I thought about just getting the race and torrington bearing(that are used with the smart shell) by themselves but I'm afraid of running into clearance issues at the front pump with the thicker beast shell and torringtons at both ends.

Greater Dimensions says that the Torrington they provide for the front pump reduces end play of the reverse input drum down to about .005". That doesn't leave much room. They say that you may need to deburr the lugs of the sun shell to provide enough clearance. I'm a little concerned since they say to use an H gauge and I don't have one. An H gauge is a sort of depth measurement tool for accurately calculating installed depth and clearance between two parts. I'll have to come up with some way of checking for clearance between the pump and the reverse input drum. Maybe if I sample fit the unit together without the output shaft, leaving the pump gasket out, and make sure that the assembly turns freely as I snug down the pump bolts without the pump gasket in place. The pump gasket is .016" thick so this may not work. I'll see what our resident guru says about it. This whole thing was his idea after all.;)
 
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