I managed to toast my transmsion this weekend.
1st and 2nd ok, but it slips like crazy in third.
I have a 1988 with a supercharged ZZ-4 and a 2800 stall converter.
Guess it was due to happen :sad:

My question is that I have a brand new (non Corvette) B&M TH-700R4 stored in my basement (part #117101).
Can I just swap my tailshaft, governer, and speedometer stuff onto this and use it?
I know the tailshaft is shorter and has mounts for the torque beam, but are their any other reasons I can't do this?
It is a 30 spline.
Any thoughts on if the B&M will hold up behind my combo.

thanks




[Modified by SuperL98, 8:18 PM 7/12/2003]

 

I'm learning now that there's a WHOLE RANGE when it comes to R4's. I'm observing the guy rebuilding my tranny now. It's a 122,000 unit that's been rebuilt once before (by another, garden variety rebuilder).

It went out after I installed the 383. I pulled the tranny, and I did the Trans-go shift kit. He's doing the knowledge critical stuff, and has done more to the tranny than I can HOPE to recall. But off the top of my head:

The pump had never been worked on, despite the tranny being 'rebuilt' before. I'd requested a Trans-go shift kit on the previous install. It's OBVIOUS that one wasn't performed based on the valve plate diameters and the colors of the springs I'd swapped out.

This tranny's getting cryo-treated parts, a Sun Shell with billet pieces, a new kevlar band on a new housing(You will not get optimum performance by just swapping the band with a broken in housing), upgraded pump parts, better clutches, all plastic shims will be replaced with needle bearings.

Why am I telling you this in detail? Because a LOT of techs want you to think the tranny is a black box that you shouldn't know about. Watching THIS guy put together a tranny is VERY enlightening, watching (and assisting) in rebuilting a 'rebuilt' tranny is ALSO teaching me a lot about the tranny industry.

So. If your B&M was built right, it'll last. If it wasn't, well....

(/me waits for the guy to chime in with the 'th400+GearVendors is the only solution' post that ALWAYS shows up in these threads)


[Modified by RocketSled, 7:55 AM 6/29/2003]

 

RocketSled you are right. When I decided to rebuild my 2004r myself I did alot of research, mostly through GN websites. I bought the ATSG manual which is cheap and has EVERYTHING you ever wanted to know and then some. I also got some advice from a local performance transmission shop- they ordered a few parts for me and charged me wholesale.

What I found out is that almost every tranny shop does is just remove/replace bad parts. Even performance tranny shops. When I told my tranny shop friend I needed some shims he questioned me- stating they never use them and it should be in spec. When I told himm how far off it was he congratulated me on the find and said he couldnt believe I checked all the clearances. This is the same shop that builds most all the perf. tranny's in the county- and has a reputation for being the "best".

This is another fine example of why " if you want it done right you have to do it yourself". I do everything to all my cars and while it takes time to gain knowledge- it beats paying an arm and a leg for half-a@@ work.

That was my first attept at building any transmission. It has the best parts i could afford, and is as good or better than the Art Carr version which sells for $1800. It only cost me +/-$900- and that includes a rebuildable core and my $400+ TCI lockup converter!! It has now logged over 14k trouble free miles on my 12 second daily driven Nova.

 

Since you have the corvette 700R4 it already has a few factory trick parts beyond the B&M. Namely the servos.

If you are thicking about doing yourself, put aside 200-300 in tools. In addition, you can upgrade your tranny for about $700 - $900. Or just say screw it and but a complete setup from PATC.

The B&M is likely to be a stock tranny with a $150 rebuild kit plus their shift kit. So unless you looking to do the job twice, just rebuild the one you have (the right way WITH MODS) and sell the other one thru ebay.

 

Guess this is all going to turn out to be for nothing.
I dug out the B&M this morning to look it over and the shift lever was frozen.
Pulled the pan and a couple of quarts of water and pink sludge came out?
All the bands are rusted, and the pink sludge is everwhere :cry :cry
The basement flooded a few years ago, must of happened then.
What a day I'm having.

Guess this post should now read:
BEST PLACE TO BUY A NEW AUTOMATIC TRANS :rolleyes:

I'll do a search, thanks


[Modified by SuperL98, 1:55 PM 6/29/2003]

 

Ummm...the B&M should have good parts in it...so you can probably just do the swapping of clutch packs and such to get your back working without any cashflow. Hopefully, just the valve body lower part is all that got rusted, just clean the rest of the stuff up and it should be fine...unless the B&M was pre-run and already had problems....


[Modified by BBA, 5:13 PM 6/29/2003]

 

Okay RockeSled, here goes: Awww, never mind. Nobody ever listens and there are always these posts about how to build a better one. I'll just keep beeting the heck outa mine then.

 

:D :smash:

 

Rebuild the tranny that's in the car now. Start with the TransGo shift kit, look at what else is outta spec (via the references mentioned elsewhere in this thread) and to EVERYTHING the instructions tell you.

I might add that what went wrong in the 700r4 was a stuck valve (no big deal) and while there was evidence of the 3/4 clutchpack getting hot, it was nowhere NEAR failure and woulda probably lasted another year or so. Since I KNEW it was in good shape, and I KNEW it wouldn't take the torque for long, I figured I'd fix it right while everything was out.

FWIW, it'll be a $5k tranny by the time I'm done with it, but It'll cost half that based on _my_ time and labor spent. (plus it'll be a 700hp unit with an efficiency loss closer to a manual than your typical slushbox.)


[Modified by RocketSled, 9:53 PM 6/29/2003]

 

Having those tools would be nice, but I rebuilt mine without any of those special tools. I took out all of the snap rings with just a dental pick and various size flat tip screw drivers. This is also the method the instructor at the community college used when I took the class. One word of caution those special tools allow for one person rebuild the method I used required an assistant (mostly one person compressing a piston while the other removes the snap ring). If you belong to a corvette club you might be able to get the club to buy the tools.

 

Looking at Probuilt http://www.pro-built.net
They seam to have lots of good feedback on thirdgen.
Prices are OK also.
They also have a rebuild parts kit.

Just took the (junk) B&M appart (to see how hard it is) and it looks like I could handle the rebuild myself.
Although it's always easier to take something appart, that to put it back together right.
I'd hate to have to pull the transmission out all over again if I messed it up.

 

I purchased one from Bowtie Ovverdrives about six months ago. It worked flawless, and hasn't given me any trouble yet. Nice firm shifts, but doesn't break your neck.

The owner (forget his name) was real easy to work with, and was very knowledgable.

Here's a link to the one I bought: http://700r4.com/trans/level3.htm

 

I have one it the ZZ4 Monte carlo SS i put together for my brother. 3000 stall and 373's. Talk about a neck snaping launch. 20k miles daily driven and no problems so far. btw, my brother dosent know the meaning of "drive it nice"