jobberone

(It comes with clutch,pressure plate,flywheel,master and slave cylinder,cross member and pedals). Will this drop into my 89 vette with stock motor and ZF 6sp without a lot of hassle. Ls1 as well assuming all the accessories.

SSLT1KID

with out hassle, no. is it possible, yes. one problem is that the link that goes from the tranny to the rear end is on the wrong side. another problem, the shifter wont come up in the right locations. ive seen it done on this website before. i was considering it myself, but didnt. with some custom brackets it can be done.

jobberone

Isn't it difficult to rebuild the ZF or to get it rebuilt properly or am I getting the wrong information? Thanks for the reply. Sounds like it's at least a little difficult.

dizwiz24

The T56 has many advantages over the ZF.

For one I consider it more 'bulletproof' than the ZF because you hear less about its synchronizers failing (I keep hearing the ZF is bulletproof except for the synchronizers. Well, if I still have to pay $x000.00 to get the synchronizers fixed, it is not 'bulletproof' to me).

Im kinda salty about the ZF because I sometimes get higher RPM gear clash (grind when going 1-2 at say 6000 RPM). I am told this is because my synchronizers might be failing. I just replaced the clutch hydraulics and hope this will cure this and that I didnt do too much damage to it already.

Some people say, oh, it sounds like your ZF was 'abused'. How exactly do you 'abuse' a transmission, especially one that is 'bulletproof'. Do you think the previous owner went out and said 'yeehaw, lets abuse the tranny tonight by not pushing the clutch pedal in all the way while shifting, shifting into reverse while going forward, etc)'....It just seems unlikely.

Also, The ZF has a lot of useless weight. I believe its at least 30 pounds heavier than the T56.

Id love to see a swap.

jobberone

I think a rebuild sounds more like an adventure. A swap sounds like a tiger by the tail for a novice like me. But who knows. Sounds like I need an LS1 with the entire drivetrain, exhaust system and accessories. Now you start thinking sell the car and just buy a C5.

I'm a newbie at this so I should take the path of least resistance. Maybe the swap of the tranny is the way to go.

bogus

I am not convinced that the T56 is better than the ZF6.

I have seen T56s blow up after 20k miles... now, most of those were a 1/4 mile at a time, but the end result is the same.

Sure, the ZF may have weak syncros, but I don't agree they are THAT weak. I am more concerned with the T56 throwing bearings than some slow dogs on ZF6.

T56s have a tendency to wear out syncros by just driving them... in 100k miles they eat themselves up. (see the story in this months issue of Corvette Enthusiast, very revealing).

a ZF will last 200k miles without any major problems (used exclusivly on the street).

Sure, the ZF is heavier, won't fight you there, but I have driven both, and I much prefer the feel of the ZF over the T56 (Fbody's).

Also, you can get a ZF built to a standard of perfection that will make it never blow.... it ain't cheap, but I believe in doing something once, and being done.

remember, there are guys out there who are running 800hp SBC's with ZFs, basically stock, and are not blowing up... try that with a stock T56.

Nothing is perfect, it's just what is more perfect than the other.

I think the biggest problem with the ZF is a lack of maintenance. If the owners changed the oil in the ZF on a regular basis, the syncros will last that much longer.

with the fitment issues of the T56, I am going to stick with the ZF...

jobberone

More very useful information. Thanks

neat

On LS1.com, a guy named RomanSS asked when the T56 was going to break in his car. He had built a 4XX cubic inch LS1, with a big N20 shot. One of the sponsors on the board told him to dyno the car, and if the T56 broke, he would GIVE him a new one. That way everyone would know the approx. breaking point of a stock T56. Roman made a dyno pull at about 975 HP, and close to 1200 Ft/Lbs and the T56 held. He has since driven the car to a 9.9XX in the 1/4 mile. The fastest LS1 6 speed in the land. Stock T56.

Unless he is planning to make an assanine amount of power, either tranny is going to work fine for him.

SSLT1KID

i think i prefered the way the T56 in my camaro felt to the ZF in my vette. plus if the stuck it in the viper it cant be bad tranny. if you really want an LS1, i think youd be better off to sell your C4 and buy a C5, but thats just my opinion. why not just modify your LT1?

rodj

Check this T56 -C4 swap out.
http://home.earthlink.net/~rontyler/t56.html

jobberone

So the ZF obviously bolts back in and is expensive to repair/rebuild and you really can't do the rebuild yourself (mostly pressed gears) and the T56 requires some fabrication to fit. Both seem relatively bullet proof with proper use and application. I do know you must use the proper lubricants, change them frequently and some swear by aftermarket additives to prolong life.

I'm waiting on information on the Richmond swap. I'm so new I don't even know what a Richmond is. Anybody care to illuminate me on the subject?

Again thanks for letting me pick your brains for this. You've all been invaluable.

jobberone

I have an 89 with the crossfire don't I. I didn't think it was an LT1 but I'm so new maybe I've got more than I think. I just got a car hauler, a 76 very nice 4x4 Cheyenne and a solid 65 El Camino that needs some restoration. So unless someone wants to trade for a C3 BB for them no more cars right now for me.

rodj

If yours is a'89 then it is a L98, 350 ci, tuned port engine (TPI not TBI as in crossfire).250 Hp / 330? Ft /lb torque

scorp508

I don't think I know a single person with a ZF6 that has gone this long without SOMETHING happening. :confused:

bogus

mine has 121k and has no problems...

racing hurts components. I have never heard of a ZF blowing up... just wearing out...

jobberone

I replaced the clutch master cylinder. Now I'm having problems with second gear grinding. Otherwise it has a full clutch pedal and shifts fine. There wasn't this constant problem with second before so when I'll try to bleed it again.

bogus

change the gearbox oil?

scorp508

Ok, come back in 79k more miles then. :)

jobberone

No. I'll try that and bleed it tomorrow. Good idea. Why in the heck didn't I think of that? :crazy:

bogus

I suggest you use Castrol TWS 10-60 in the tranny... it does help.