Cascade Crew

Xecris · Posted: Sun Dec 06, 2009 2:15 pm Post subject: Transmission gurus

Last summer, I lost 3rd and 4th gear in my 700r4, so I replaced it with a used transmission until I could get this one figured out. I started disecting it today, and can see that the band is badly worn (chips in the friction material and general glazing all over it). The clutches also have some pitting and glazing on them, and some of the steels are burnt up looking.

Now, I have never rebuilt a 700r4, or even seen the insides of one. I am pretty handy with a wrench, and hoping that this is not too far over my head. I have yet to pull the planetaries - back out of the trans. Is there any more clutches or anything really worth pulling out from the rear, assuming the clutches are the sole reason I lost my gears? I guess they'll have to come out for cleaning. The planetaries look to be in perfect condition (new about 700 miles ago).

The trans died when the ratchet assembly on the TV cable went on me, shop said there was not enough pressure in it to hold 3rd and 4th. Does this sound reasonable? Again, I am not a transmission guy, but I have been researching off and on since I pulled it.

The big question here is - If the hard parts are in good order (drum is still straight, no cracks), could I get away with giving the transmission a good cleaning and buying new clutch packs, torque converter and a band? I am not trying to cut corners, but everything in the transmission was new 700 miles ago. Supposedly. Is there anyone here with 700r4 experience I could bounce questions off?

The slightly smaller question is - If I can go through with doing the clutch packs, are there any specialty tools I *will* need to finish this? I've got a garage full of tools, but no transmission-only tools. Any tips or tricks? I haven't really found a good source for this kind of information, aside from ordering up an ATSG. The clutch packs don't look that imposing from the outside, but you never know...

I've attached a picture of where I am at now. Any help would be appreciated.

Twilightoptics · Posted: Sun Dec 06, 2009 2:23 pm Post subject:

Talk to these guys:
http://www.700r4l60e.com/

Xecris · Posted: Sun Dec 06, 2009 2:49 pm Post subject:

I've talked to Dana a few times, but he seems a little against me trying to take this on myself without any experience with transmissions. But, that was a couple months ago, he might be a little more willing to help me through now that I have it torn down a bit.

Twilightoptics · Posted: Sun Dec 06, 2009 2:51 pm Post subject:

Well if all the hard parts are fine, you're just doing a typcial shop rebuild by replacing bearings/seals/bands/clutches etc all the wear items.

I'd recommend a step by step book. Brandon would know about needed tools. There are lots of little things to look for as far as wear of hardparts that a book and or experiance will tell you.

chevymad · Posted: Sun Dec 06, 2009 4:16 pm Post subject:

There are several puller type tools that you'll need. I ended up making one, then modifying it as I got deeper into the trans. I think I needed it 3 or 4 times before everything was apart. I can't remember exactly what I ended up with. But was fairly easy to figure out what I needed to do by looking. I rebuilt mine using the ATSG manual. I upgraded several parts while I was in there, and replaced all the bushings while I was at it. I went with a wider band, Beast sunshell, upgraded stator, corvette servo, upgraded pump rings, and I got a shiftkit from Dana. I just used a rebuild kit from napa, but after reading more about it, I probably shouldnt have. The napa kit has the cheap brown clutches. I havent had any problems though. I recommend against using the 4th gear wot holding tv assembly. You'll find it wants to stay in 4th and bog instead of shifting to 3d on a pass many times. Also the new tv assembly is manufactured slightly large to make up for a worn valve body. If yours isnt worn.. guess what? it sticks. TV cable adjustment is critical to the life of the trans. Just a few clicks off and you'll burn it up.

I tried a superior shift kit before ordering dana's. I dont recommend it either. It came with a vette servo but wanted you to modify it. So I followed directions and it didnt work right. Ended up having to put the original back til I got a new vette servo. Dana's version of the transgo kit is very nice.

Xecris · Posted: Sun Dec 06, 2009 8:25 pm Post subject:

Sounds like I'll definately be needing a good book on this, then. Going to see what I can dig up, a coworker might have one he can loan me. The clutches I pulled out of the transmission were all red (red alto?). I already have a transgo kit in there from Dana, so I'll look into some other upgrade options while I am in there. In all honesty, the only reason I'm going to go my own on it is because I can't afford a fullout rebuild from a shop (Hey, it is how I learned everything else Cool

). Dragging the laptop to the garage and taking step by step pictures is sure to help too.

chevymad · Posted: Sun Dec 06, 2009 9:06 pm Post subject:

Same way and reasons i did mine.

izcain · Posted: Fri Dec 11, 2009 6:48 pm Post subject:

I've rebuild quite a few of those transmissions and I would say go for it but be sure to use all the better parts. Since your saving money on labor, and you can take your time I would buy all of the best stuff and build it up stout. Don't screw around with stock sunshells and stuff get "the beast" sunshell as they call it. Also make sure that you run with alto fibers and kolene steels. A good overhaul kit from TCI or the like will have some quality clutch's in it and will include extra fibers and steels even so you can get the more holding power.

I built a 700 a while back for Z and it stood up to about 20k of total torture abuse and choas lol

My built consisted of:
1988 Casting (should have later 80's casting due to improvments in the oil passagways!)
TCI overhaul kit
Added clutch packs
Kevlar band
Beast sun shell
Jet servo (much larger then Corvette)
.500 boost valve
TCI reverse manual valve body (at a certain point this is a must since when you are trying to put ALOT of power down the transmission has a hard time keeping the automatic feature due to TOO MUCH line pressure
A TCI pan and Derale cooler (a must since most 700 operate at a much higher degree then most others in the Turbo Hydramatic family)

and a B&M converter (It's all I had laying on the bench and it was new!)

Let me know if you need some help I have some original GM manuals on the 700 from when I was working @ GM I would be happy to try to copy some of the stuff

Judging by the pic your not very far into the trans yet. I would tear that thing down to a bear case and start from there!

chevymad · Posted: Fri Dec 11, 2009 6:54 pm Post subject:

Forgot all about the 2 boost valves. Also I saw several performance builders say to watch adding too many clutches and steels to certain gears. I guess they were making them too thin causing burning and warping. I think they recommended thinner clutches but standard thickness steels..

Rebuild kit I used was for a 4l60e.. so it had a few upgraded components as well.

izcain · Posted: Fri Dec 11, 2009 6:57 pm Post subject:

If I remember right you can add one extra pack without causing any adverse effects. It's when you start machining the apply pistons down to gain more clearance that's when you start causing the problems.