Hit low gear in PG at 140+mph

[68Bird]

Hey Hutch,
I have a 'friend' that accidentally bumped the shifter into 1st going thru the traps at 140+ for maybe a second. Didn't do anything noticeable in the car. What would that do to the trans? It's a glide by the way. I assume it would 'try' to apply the band and it wouldn't be able to grab and maybe I'd (or my friend I mean) would just loose a little band material? Any permanent damage? Stupid, I know. :smt073


Thanks.
Craig

[Hutch]

For sure the trans is wounded. It may live for awhile but it won't cure itself. Its early in the season, when your buddy gets a chance, he should get it looked at before it makes more of a mess.

Hutch

[68Bird]

Thanks for the reply.....can you elaborate a little more on what it did and what could happen down the road?

Thanks,
Craig

[Robert1320]

Craig what did he do that for???

[68Bird]

Hey Robert......dammit, I don't know. It was on the first pass after a loooooong winter.....guess someone had a flash-back of the days of running a manual trans car or something. <bang head against wall>

Craig

[Hutch]

It basically charred the band and possibly the drum. It will just start to wear much more rapidly now and you will be getting more and more crud throughout the entire trans fluid system. Hopefully its not too bad but I always assume the worst.

Hutch

[68Bird]

Ok. Thanks Hutch. We'll get her checked out I guess. I need to start buying trans fluid in 50 gal drums. Get 4 passes, trans comes out (cracked drum), 4 more passes, pull it again (blown up planetary), 6 passes, out it comes again,.....lather rinse repeat. I want a Liberty....

Craig

[Robert1320]

Check you local industrial Lube supply houses.
Many sell the fluid you need in drum.

[68Bird]

Assuming the band is toast, what should I replace it with? I have to order some stuff from Jegs soon and was thinking of getting either the TCI Kevlar band or the TCI High Energy band. I'm pretty sure it has a standard TCI Kevlar one in it now. Also, they cost between $50 and $80, is that an avg. cost or can I get one significantly cheaper somewhere else?

Thanks,
Craig

[Hutch]

Either band is good, I think the hi energy series is a little more money and a better material. 50-80 bucks sounds fair , im sure there is something cheaper if you keep looking but not by much.

Hutch

[68Bird]

Well, got it pulled apart. Drum didn't look bad. The heat mark in the center polished out easily with some 120 emery cloth. The band doesn't look bad, but the center is smooth or kind of glossy compared to the outside. Should have a new band in the mail today just to be safe.

Couple questions:
1. Why does it appear that only the center of the band is wearing and not the outside? Is that typical?
2. In the high clutch steels, the one that goes in the bottom of the drum has 2 little notches in the locating tabs. You can kind of see it in the top steel in the second pic. Are these supposed to be indexed a specific way when I put it back together like they are in the reverse clutch steels? The notch doesn't appear to need to line up w/ anything in the drum.
3. The high clutch clearance was measured at .060" which from what I've read seems tight for a 7 clutch drum. Should be closer to .070" according to Carl Munroe's book. Is this too tight?
4. Should I put 8 clutches in high and ditch the last steel, using the sun gear flange for the last steel?

Thanks,
Craig

[redvictor]

Well, got it pulled apart. Drum didn't look bad. The heat mark in the center polished out easily with some 120 emery cloth. The band doesn't look bad, but the center is smooth or kind of glossy compared to the outside. Should have a new band in the mail today just to be safe.

Couple questions:
1. Why does it appear that only the center of the band is wearing and not the outside? Is that typical?
2. In the high clutch steels, the one that goes in the bottom of the drum has 2 little notches in the locating tabs. You can kind of see it in the top steel in the second pic. Are these supposed to be indexed a specific way when I put it back together like they are in the reverse clutch steels? The notch doesn't appear to need to line up w/ anything in the drum.
3. The high clutch clearance was measured at .060" which from what I've read seems tight for a 7 clutch drum. Should be closer to .070" according to Carl Munroe's book. Is this too tight?
4. Should I put 8 clutches in high and ditch the last steel, using the sun gear flange for the last steel?

Thanks,
Craig

1/ usually aftermarket bands are not round,particularly the "no name" ones.They tend to grab either just the centre or just the outside.Best Kevlar one i have seen is the Sonnax standard width one.
2/ Far as i'm aware you line them up with each other in a stock drum to let the oil drain out... as you have a stock drum maybe line them up.Hutch will know for sure...
3/ 010" per plate is specified.
4/depends what power you have.More clutches= more drag. Engine size/power?torque? If there is no burning on them maybe 7 is enough...
Hope that helps....

[68Bird]

Can you tell by this pic what kind of band that is? Last rebuild it had a kevlar one, this one my guy put in last time looks different. Has BWA cast into the steel tab, and some numbers stamped on the back. I'm putting a new BTE kevlar band in it.

I think the 7 clutches seem to be holding ok so far, nothing but a few tiny hot spots on some of the steels after 15-20 passes. See car details below....pushing around 1000hp.

Craig

[redvictor]

Can you tell by this pic what kind of band that is? Last rebuild it had a kevlar one, this one my guy put in last time looks different. Has BWA cast into the steel tab, and some numbers stamped on the back. I'm putting a new BTE kevlar band in it.

I think the 7 clutches seem to be holding ok so far, nothing but a few tiny hot spots on some of the steels after 15-20 passes. See car details below....pushing around 1000hp.

Craig

Maybe 8 would be good.What pressure are you running in the trans? have you checked? does the trans flair slightly on the shift?
At that level 180 to 200psi is good.
I can't tell what band is in the photo.Can you take it with a flash to highlight it?
Like i said for me the best kevlar is the Sonnax.It says Sonnax all around the lining when new.....

[68Bird]

Haven't checked pressure, need to rig up a gauge so I can do that in the car. Doesn't seem to flair on the shift from what I can tell. However, looking at my last log in my digital 7, my shift rpm was 7000. Funny thing is my light was set at 6000. I know I'm probably a few hundred slow but 1000 slow is alot. But band slippage after my little 'incident' may have contributed to that.

Do I check the pressure at the servo port or the rear (reverse) port? Car idling in park?

[redvictor]

Haven't checked pressure, need to rig up a gauge so I can do that in the car. Doesn't seem to flair on the shift from what I can tell. However, looking at my last log in my digital 7, my shift rpm was 7000. Funny thing is my light was set at 6000. I know I'm probably a few hundred slow but 1000 slow is alot. But band slippage after my little 'incident' may have contributed to that.

Do I check the pressure at the servo port or the rear (reverse) port? Car idling in park?
pressure is checked at either rev or servo port.Trans in low or rev dependant on your choice of port.
Hold your foot on the brake and build the revs a little.DONT floor the throttle...then check what you have on the gauge.I'd check both to make sure pressure is right in both circuits.
i'd be slightly but not overly concerned if i had a 1000rpm flair.Does it tell you how many 1/10's of a second that is over on the digi7?
sometimes there is more than a pressure issue. Check it and let us know what it is..

[68Bird]

Will do, thanks for the help! Should have it back together and running tonite or tomorrow and will check the pressure if I can rig up a gauge at the hardware store. I'll have to look at my log and see how much time it took for the rpm flair too.

Craig

[Hutch]

7 clutch setup is nice, deglaze the steels before reinstalling them. That drum finish looks a little rough. The band is burnt in the center because you put it in low at 140 mph BUT got it back in high pretty quick before it had time to really get a hold of that drum and make a bigger mess. Check the pressure from the servo port this will tell you , low, high and transbrake pressures. 180-220psi would be a good start. Set the band to 4 turns and go racing.

Hutch

[68Bird]

Thanks for all the help guys! This was the first time I've had the trans apart myself (partially anyway) and it was a huge learning experience. Got everything back together and trans back in the car last night. As soon as I get a pressure gauge I'll check it at the servo. Going to the chassis dyno Saturday.

Craig

[Robert1320]

Thanks for all the help guys! This was the first time I've had the trans apart myself (partially anyway) and it was a huge learning experience. Got everything back together and trans back in the car last night. As soon as I get a pressure gauge I'll check it at the servo. Going to the chassis dyno Saturday.

Craig

Right-on! Let us know the good new Saturday!