I wanted to race this guy so I popped it into 1st so I could manually shift at high rpms.. and at WOT the thing shifted to 2nd at around 4000rpm while it was still in 1st. Its been doing this lately, anyone know what the problem could be?

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87 Camaro Sport Coupe
2.8L Auto, MSD Coil, Crane Cams 8.0mm wires, AC Rapidfires, K&N Filters, Brakes 100%
Z28 Hood and Rims

 

In the stock condition the 700R4 (no valve body modifications) will not hold first gear with the standard (V-8) governor. Where does your transmission shift at WOT in the drive or overdrive position? Make sure the the TV cable is adjusted as per transfixleo's recommendation. If you want later shifts in the drive position, then change to a lighter weight governor. If you want to hold first to any desired rpm, then you will have to install the Trans-Go Performance Shift kit. This kit does the modifications to overcome the not holding in gear problem.
Hope This Helps!!!

 

Hmm I'll have to check that to be sure, but the last I remember my tranny will shift higher in drive than it did when starting in 1st. I try not to have it in OD unless I'm going 50mph or more and cruising. When the 700r4 downshifts from 4th it sits in neutral for a couple seconds before it hits 3rd, which a guy from a tranny shop diagnosed that my clutch was burning out and in about a year or so depending on how I drive I'll need to rebuild the thing. He said to try and keep out of OD unless I'm on the highway.

 

Watch out, if your tranny flares on a kickdown from 4th to 3rd it is likely that the sprag is slipping. Worst case scenario is it can take a bunch of parts out when this happens. The sprag wears in normal use and if you have lower gears it is even worse. It could too be that the Forwards are breaking away on the downshift too. The Kit that Pro Built talks about is a great idea but if your sprag is bad it can't help that. For now, manually downshift to third then hit it and see if it holds.

 

Thanks for your reply transfixleo...

My stock rear end gears are 3.42's. This sounds bad about the sprag.. transmissions seem very complicated to me at my stage in automotive education, but is it possible to replace a worn out sprag without extensive work or is it pointless without rebuilding the entire tranny if it must be opened? Also what is it you mean by "see if it holds"? In reference to manually downshifting to 3rd from OD and hitting the gas.

I'm concered with keeping my tranny alive for as long as possible because I will be going to college this september. Would that TransGo shift kit help the life of it at all? Also I'm sure it would be a bit of fun too

Today I adjusted my TV cable like you've explained in other posts (I actually have a 4 month old TV cable from the dealer because my last one didnt want to adjust at all) and it seems to shift a bit smoother. At WOT the 700r4 shifts to 2nd at 4,500rpm and to 3rd at 5,800rpm.

Thanks a ****load

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87 Camaro Sport Coupe
2.8L Auto, MSD Coil, Crane Cams 8.0mm wires, AC Rapidfires, K&N Filters, Brakes 100%
Z28 Hood and Rims

 

Wow, this sort of verifies the conclusion that I've come to on my situation, although it seems to happen more to me on upshifts from 2 to 3. I really don't think it's the 3-4 clutch pack because it hooks back up pretty hard. I also have the problem more when the trans is cold, and with a little physics thrown in, it would make sense that it would be better when warmer (round objects increase their diameter as the temperature rises, therefore making the sprag "tighter"). This makes sense to me, but if I'm way off here, I'd like to know for future reference.

Thanks.

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Working on:
'84 Z28 LG4 305 with 200,000 original miles!
Added dual elec fans.
145 MPH IROC Speedo
Building 430 HP 350 (ZZ430)
using primarily GMPP parts.
Short block sitting on a stand. (Man, those Fast-Burn heads look good, (just sitting there doing nothing!LOL))

Starting to look like the Kicker poster child!

ASE Certified Master Tech

 

To replace the sprag you need to take the tranny out and apart so as long as you are there...

 

I've checked out that 'dogbone' sprag in there and that thing is a precision play toy...

It's strange how that thing actually locks on a smooth slippery oil coated surface. It's amazing it works turning it in my hand let alone engine power! But by design the more reverse rotation applied the harder it grips...

What makes this thing slip besides all out breakage? does the diam. of the housing for it wear out, or is it more or less the sprag itself.

I guess I'm amazed at stupid things... the roller sprag doesn't exite me much.

ohh.. you have to tear about 70% into the thing to get at it, so a rebuild only makes sense.

 

matlock you are getting screwed out of alot of your cars power. the redline is @ 6000. I have a similar problem. I need to take care of it.

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1988 Camaro Sport Coupe
2.8 V6, TCI 3200 Stall TC, B&M Transkit, 80 Series Flowmaster & Catback,'83 CFI Z/28 Hood,
'87 16" IROC Wheels on Kumho Ecsta Supra 712's, '92 Z/28 Bowtie Grille, IROC Gauges, IROC Taillights,
IROC Foglamps w/ retrofitted 9005 hi-beam headlight bulbs
*NEW* Just Painted -- Heritage Style Hood and Decklid Stripes -- *NEW*

 

Yeah I think my car is suffering from it. I've noticed that from 1-2 the tranny is slipping a bit. But at WOT I guessed the 2-3 shift was around 5800rpm but I let off the gas a bit. Today I pushed it and it went to 6000rpm and still wouldnt shift to 3rd so I let off the gas a bit and let it shift. Weird I thought it would only not shift to OD at WOT.

 

The reason it wears is, by design in fourth gear the sprag overruns and while doing so, the 'sprag' elements rub against the races and then when they reapply, tht action is kind of rough on them, especially at speed. The 1st generation 700 had a roller clutch instead of the sprag but they quickly found out that it can't handle high rpm! The thing is though that they don't wear like a sprag but they also don't have as much strength. When I get one, I save it for a diesel since they never get to high RPM's.



[This message has been edited by transfixleo (edited June 06, 2001).]

 

Yeah, i figured mine has the roller clutch, and that was what I was speaking of. I think it is my problem though. The trans. is coming out when the new engine goes in, (Maybe sooner) and I'm putting one together to replace it, using a 1988-up core.

Thanks for all the great info we're getting here!

------------------
Working on:
'84 Z28 LG4 305 with 200,000 original miles!
Added dual elec fans.
145 MPH IROC Speedo
Building 430 HP 350 (ZZ430)
using primarily GMPP parts.
Short block sitting on a stand. (Man, those Fast-Burn heads look good, (just sitting there doing nothing!LOL))

Starting to look like the Kicker poster child!

ASE Certified Master Tech

 

Was there an update in 1987 for this? I can hold 1st gear to any RPM- but I've got an '86 transmission. Or- is it because I have the V6 model?


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-Tom P (Hot rodded 1986 Firebird 2.8l) from http://www.f-body.net/mailbag/3rd/3rd_mailbag.html message boards
---Think your car could be pic of the week? Visit http://www.f-body.net for details!

 

The roller input clutch was only on the very first generation 700's in early '82. After that they went to a sprag and are now on their 3rd version sprag which seems to be a real winner!

The V-6 will rev allot higher than most V-8's but all stock 700's will upshift out of first at some point.



[This message has been edited by transfixleo (edited June 09, 2001).]

 

Explain this one!! Since my trans has been rebuilt, it has a serious flare of rpm's between 3-4. It is a 1989 700r4 with a trans go shift kit in it. But it also doesn't make neck snapping shifts. But the shifts are quick when driving normally but when I hammer it the shifts get way too soft for my likeing. I rebuilt the trans in school and my teacher thinks that I cut a seal in the trans somewhere. The reason for the rebuild ws it had 225000 miles on it and had spare time in class. Any ideas?

 

If you mean a long shift then yes, it is possible that you damaged the Teflon seal on the 4th Serv (in cover). If it literally revs up for an instant I would be looking at a Forward Clutch or 3-4 clutch problem. When you go to 4th the only change is that the Band comes back on. The 3-4's are still the driving member, while the Forwards overrun through the sprag.