Any quick/easy way to diagnose a failing 700R4?
Thread Starter
Member
Joined: Jul 1999
Posts: 496
Likes: 0
From: Chicago, IL
Car: 89 IROC-Z
Engine: LB9
Transmission: 700-R4
Any quick/easy way to diagnose a failing 700R4?
I'm about 90% sure that my trans is slipping and on the way out. It stumbles a lot from gear to gear and sometimes won't shift until it revs really high but this revving doesn't produce quick acceleration. My dad thinks I might have just screwed up a vacuum hose or something when I swapped the intake, but I'm not even sure the 700R4 uses any engine vacuum to operate, and isn't the TCC the only computer controlled part? Thanks for any help, the HELM manual diagnosis is quite daunting so I don't know where to start with that, and I've heard firsthand that some shops tell their techs that whoever comes through the door gets a trans rebuild (yikes).
Also, I've found a guy that does rebuilds after hours (have it from a good source that his work is excellent) for cash and he said if there's no planetary damage he could do a basic rebuild for $300-400. Does this sound right? He said that's if I remove/reinstall the tranny, or else it would be $150-200 more.
That said, if I have this thing rebuilt, what are some goodies to put in there? He said a shift improver kit would be a good idea, and I'm also going to spring for a vette servo and upshift valve. When it's said that a tranny can handle X amount of horsepower, what goes into that number? I'm basically looking to support a little over 400 horsepower unless it's going to cost too much.
Thanks for any and all advice!
------------------
Base: 89 Iroc-Z LB9 auto 2.73 posi
Exh: 3" Dynomax muffler, 3" Pipe in place of cat
Ign: Accel 300+ wires, cap&rotor
Fuel: Cleaned and flow-matched injectors, afpr, !air pump&diverter valve
Sound: Clarion deck, Kicker speakers and amps
Suspension: KYB Shocks, BMR Strut Tower Brace
Misc: TB Bypass, Synthetic Oil, Flexlite Transmission cooler,
free mods, hopefully engine swap and 4th gen seats in the works...
[This message has been edited by I ROCK (edited January 27, 2001).]
Also, I've found a guy that does rebuilds after hours (have it from a good source that his work is excellent) for cash and he said if there's no planetary damage he could do a basic rebuild for $300-400. Does this sound right? He said that's if I remove/reinstall the tranny, or else it would be $150-200 more.
That said, if I have this thing rebuilt, what are some goodies to put in there? He said a shift improver kit would be a good idea, and I'm also going to spring for a vette servo and upshift valve. When it's said that a tranny can handle X amount of horsepower, what goes into that number? I'm basically looking to support a little over 400 horsepower unless it's going to cost too much.
Thanks for any and all advice!
------------------
Base: 89 Iroc-Z LB9 auto 2.73 posi
Exh: 3" Dynomax muffler, 3" Pipe in place of cat
Ign: Accel 300+ wires, cap&rotor
Fuel: Cleaned and flow-matched injectors, afpr, !air pump&diverter valve
Sound: Clarion deck, Kicker speakers and amps
Suspension: KYB Shocks, BMR Strut Tower Brace
Misc: TB Bypass, Synthetic Oil, Flexlite Transmission cooler,
free mods, hopefully engine swap and 4th gen seats in the works...
[This message has been edited by I ROCK (edited January 27, 2001).]
Thread
Thread Starter
Forum
Replies
Last Post
[CA] 700R4 trans & parts
6998poncho
Engine/Drivetrain/Suspension Parts for Sale
0
Sep 25, 2015 02:56 PM





