T-56 major problems need help???

[miller456]

Last night i was racin some built 5.0s and made the great mistake of dropin from 3rd to 2nd instead of goin to 4th :brick: yea i know. Well now i can smell exhaust fumes somethin horrible and i believe the tranny is knockin but i drove it 30 min home that night and all the gears shifted fine, my clutch seemed normall but the car idles at 500 rpms the whole motor and tranny shake and its knockin but i cant pin point it. I really hope u guys can help me out? thanks in advance. Oh and by the way i pulled 2-3 cars on the built stangs and got it on tape to so it was still a good night :D

[96z28]

it might not be the tranny. These trannys are strong. You probably bent a pushrod

[35thAnniZ28]

the FOOTAGE!

[jad628]

it might not be the tranny. These trannys are strong. You probably bent a pushrod

Agreed. Sounds like you over-revved and bent pushrod(s). Rev-limiter can't help when you do that.

Hopefully, you can get it fixed cheap.

[miller456]

Agreed. Sounds like you over-revved and bent pushrod(s). Rev-limiter can't help when you do that.

Hopefully, you can get it fixed cheap.

Yea u guys are proble right i dont believe the pushrods are too big of a deal to replace i will proble do it myself and buy some chromeolly compcam pushrods off ebay all 16 for $100 shipped does that sound reasonable and how hard is it to change them?

[96z28]

also u said you heard a knock maybe you need to replace your tranny mount

[jad628]

Yea u guys are proble right i dont believe the pushrods are too big of a deal to replace i will proble do it myself and buy some chromeolly compcam pushrods off ebay all 16 for $100 shipped does that sound reasonable and how hard is it to change them?

The price sounds okay, but I've not had the privilege of replacing mine (and I hope to keep it that way). If it's like anything else on an F-body engine, the cowling will probably be the biggest pain. I haven't heard of the pushrods being a big deal on an LS1 valvetrain.

[miller456]

also u said you heard a knock maybe you need to replace your tranny mount

That could be i will crawl under there again today and see i find ne thing i know it was shakin like a mad man when runnin but so was the motor and with the bent rod im sure the tranny mount is ok but u could be right. Thanks for all ur guyses help and if ne one knows the easeist way or ne tricks on changing these please let me know.

[96z28]

Tranny mount is more elbow grease than anything. When i changed mine all i knew was where it was. Pretty simple. Im sure if you do a search youll find a how-to page. Im too lazy to type all of it anyways

[miller456]

wow i took my rods out 6 of the 16 rods were extremely bent and the others might of had a slight bend that i couldnt notice so i got all new rods, plugs, and plug wires while i had crap torn apart i will let everyone know if my probems go away.

[jad628]

wow i took my rods out 6 of the 16 rods were extremely bent and the others might of had a slight bend that i couldnt notice so i got all new rods, plugs, and plug wires while i had crap torn apart i will let everyone know if my probems go away.

Holy high RPM Batman!!!!


Check your valves and springs too. Make sure none of them were damaged.

Did you go back with OEM pushrods or did you use stronger ones?

The reason I say that is the whole reason the pushrods bend is valve float. The stock springs are only good for around 6200 rpm and any more than that causes the valve to hang open momentarily because the return spring isn't strong enough to keep everything synched. The play gets the pushrod slapped instead of pushed and it can bend. I mention the valves because they were likely slapped closed by the piston. More often than not (I hear), the valves are okay, but a broken spring is a possibility. Might as well look at 'em while she's opened up. Aftermarket springs are a quick and effective way to bump up safe rpm limits. Seems like 500 rpm more is the norm. Still, the mechanical excess of rpm's that you probably did was in the 7300 range. That will take a lot more to handle!!!

Good luck.

[miller456]

Holy high RPM Batman!!!!


Check your valves and springs too. Make sure none of them were damaged.

Did you go back with OEM pushrods or did you use stronger ones?

The reason I say that is the whole reason the pushrods bend is valve float. The stock springs are only good for around 6200 rpm and any more than that causes the valve to hang open momentarily because the return spring isn't strong enough to keep everything synched. The play gets the pushrod slapped instead of pushed and it can bend. I mention the valves because they were likely slapped closed by the piston. More often than not (I hear), the valves are okay, but a broken spring is a possibility. Might as well look at 'em while she's opened up. Aftermarket springs are a quick and effective way to bump up safe rpm limits. Seems like 500 rpm more is the norm. Still, the mechanical excess of rpm's that you probably did was in the 7300 range. That will take a lot more to handle!!!

Good luck.

I believe all the valve springs were ok and yes i purchased comp cams chromolly pushrods i didnt want to buy crap again when ive got it torn apart. I also purchse some 10.4mm taylor plug wires and new plugs so im hopin all goes well when i get my orders in. Thanks for you help i will check everything again when i get home it was gettin dark last night so i quit, i will update u later.

[pocheasy]

That could be i will crawl under there again today and see i find ne thing i know it was shakin like a mad man when runnin but so was the motor and with the bent rod im sure the tranny mount is ok but u could be right. Thanks for all ur guyses help and if ne one knows the easeist way or ne tricks on changing these please let me know.
also check out the tq arm mount while your under there

[jad628]

I believe all the valve springs were ok and yes i purchased comp cams chromolly pushrods i didnt want to buy crap again when ive got it torn apart. I also purchse some 10.4mm taylor plug wires and new plugs so im hopin all goes well when i get my orders in. Thanks for you help i will check everything again when i get home it was gettin dark last night so i quit, i will update u later.

No problem, heck you're one-up on me. I know about it, but never had to replace 'em!!!

[96z28]

hey miller456, when you bent them rods did you hear some kind of ticking noise when the engine was cold? Maybe is not a ticking, it sounds more like a quiet slap. The reason why i ask is because my engine makes that noise

[miller456]

hey miller456, when you bent them rods did you hear some kind of ticking noise when the engine was cold? Maybe is not a ticking, it sounds more like a quiet slap. The reason why i ask is because my engine makes that noise

Yes i did have a knocking but it did it no matter what temp the car was at. Also it would run smoother at about 2k and make that exact noise ur describing but u have to understand i bent almost half of the 16 rods pretty good so my idle was super rough and had a bad exhaust leak cuz most of the bent rods were on the exhaust side. If you had a bent rod like that your SES light would come on and flash at you and the car most likely would idle rough. If you have ne more ?s let me know. Also i believe what you are hearing is the normal piston slap that a lot of our ls1 cars make from factory and its just something GM has said is normall.

[96z28]

Yes i did have a knocking but it did it no matter what temp the car was at. Also it would run smoother at about 2k and make that exact noise ur describing but u have to understand i bent almost half of the 16 rods pretty good so my idle was super rough and had a bad exhaust leak cuz most of the bent rods were on the exhaust side. If you had a bent rod like that your SES light would come on and flash at you and the car most likely would idle rough. If you have ne more ?s let me know. Also i believe what you are hearing is the normal piston slap that a lot of our ls1 cars make from factory and its just something GM has said is normall.



Yeah that was what i was thinking. I guess is time for a louder exhaust so i can avoid hearing it

[miller456]

Yeah that was what i was thinking. I guess is time for a louder exhaust so i can avoid hearing it

:hahano: there ya go, what kind of exhaust do u have now or is it just stock? I have corsa and love the way it sounds even w/o headers. Get ya some good exaust and a few more mods and u wont have to worry about hearing it ne more.

[96z28]

getting true duals pretty soon, might also get LT's but dont know for sure

[miller456]

Very nice hopefully all goes well for u then the LTs would be really helpfull to get rid of that crappy stock y pipe we have.

[thecorrectformula]

Hey Miller I'm about to replace my Pushrods. How hard is it to get at the back few rods. and How long did it take to replace.

[miller456]

Hey Miller I'm about to replace my Pushrods. How hard is it to get at the back few rods. and How long did it take to replace.

Well it took me completely about 2 hours cuz i didnt have the right tools and had to drive around to get tools. All in all id say about 1 hour and i wouldve had all the rods out and keep in mind this was my first time. Its not too tough but make sure you have extensions for your wrench it makes it much easier to get to and the back rods were not to bad cuz i used a cheater bar, u just slide another bar over ur wrench for leverage. The most pain was getting the valve covers off the pushrods are simple. If u have ne more ?s just let me know, good luck.

[miller456]

Well i got the new rods, plugs, and wires in yesterday and wat a pain in the :moon: the back 2 plug wires are on the passenger side to get to. I had a 2000 z28 that seemed much easier when i did that one now my 1998 sucked. Anyways the motor runs smooth and great now but we also discovered the chatter as i suspected was a bearing out in the tranny. I guess its time to give sixspeedsinc a call.

[menardst]

Hey Miller,

I am not sure, but I looked around for the best price for a t56 rebuild and found this guy Chris Jennings in TX. His prices are unbeatable as far as I know. I ordered the extended performance upgrade from Jennings Race Performance and so far it is great.

Good luck and I hope this helps.

[miller456]

Hey Miller,

I am not sure, but I looked around for the best price for a t56 rebuild and found this guy Chris Jennings in TX. His prices are unbeatable as far as I know. I ordered the extended performance upgrade from Jennings Race Performance and so far it is great.

Good luck and I hope this helps.

Hey thanks for the advice how has your tranny worked out for u from them? You should check out sixspeedsinc.com they are out of houston, tx and have incredible packages and customer service. The one im lookin at is just their
1+ package and you have to break 700hp to void warranty. Also right now they are paying for shipping both ways this month and the complete rebuild is around 1200 with mikronite finish. I will do some checkin and appreciate the help u should check out that site i gave and see wat u think. Also they have the fastest N/A ls1 running low 9s right now.