4 speed to 4 speed od clutch chatter

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racerkilla

racerkilla

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So I have a 4 speed in my duster(2.66 I think first gear) and it works flawless. It is a 340 with a new flywheel, mcleod clutch, new z bar bushings, motor/tranny mounts, u joints and 3.55 gears. I swapped the 4 speed over yesterday to a od 4 speed I picked up. I had the od 4 speed apart and bearings look nice shape, put new synchro, 3 tabs and 4 new springs in it. The pilot bushing I use in the roller type that fits in the converter bore.

The 4 speed od with matching bell. When cold has a bit of chatter taking off easy in 1st. Once everything is warm the chatter is so bad I can't even get the car to move in first. Either riding it high rpm or even low shakes entire dash. If I take off in second I can get the car to move by riding the clutch(it is smooth doing it like that). The input bearing has very little play, the main shaft and rollers looked prefect shape.

Today I pulled the od 4 speed back out, checked the clutch for oil(it is spotless clean with no heat spots) and re used the od bellhousing. I used an a230 3 speed retainer on my original 4 speed that is a bit over 5in to match the bellhousing. I figured maybe bellhousing had something to do with it. The od bell with large retainer on my original 4 speed does not have one shake or chatter no matter what I do

Has anyone ever had any issue like this.. Is it from the different 1st ratio.
 
It's not from the different 1st ratio. Sounds to me like a clutch adjustment or alignment issue. The OD bell may not be aligned properly. They're also different enough that the clutch adjustment may need to be altered. The clutch fork is also a little different from the standard A33 to the A33OD, the pivot is different, etc. Not much, but again if you're using the 833 parts with the 833OD bell you may have some adjustment issues. Also, did you change the yoke? Some of the 833OD's use a different rear yoke than the 833. If you changed the yoke you may need to rebalance the driveshaft.

Pictures are all from Brewer's.

A33 fork
CF1106N-1.jpg


833OD fork
CF-BALL.jpg


833 pivot
FP848.jpg


833OD pivot (car)
FP859.jpg


833 OD pivot (truck, but same bellhousing casting number as above)
FP859T-1.jpg
 
Only fork I have is the one from an o/d 4 speed car. I used it for 5 years with a normal 833 bellhousing with small retainer with plain 833

So I did have an o/d fork, od bellhousing with correct pivot with the od trans.

What gets me is I kept the OD bellhousing on the car today, the same fork/throw out bearing I used with both transmission. The same free play for the clutch and It does not chatter with my original 4 speed. I used a 3 speed retainer on my original 4 speed(small bolt pattern with the 5in plus diameter) so I could make sure bellhousing wasn't causing issues.

If it works perfect right now with a standard 4 speed, od bell, fork I have along with the other parts then I should be able to un bolt trans,swap just the box and should be the same. Not the case
 
Also using same driveshaft, pinion angle, yoke, u joints, shifter and rods.I just had to make a longer one for 3/4 because of the flipped lever

Basically only swapping one box for another. I know its not the od bellhousing or anything bellhousing forward as it works flawless with my original box(with larger retainer now). Just got in from driving it
 
I had a severe chatter issue like you are describing with my big block 4 speed 1968 Dart. I converted from a 273 auto to that. I could not pull out without the whole car shaking violently. Another guy down the street had the same problem with a 440 when he converted to a 4 speed. It took me about a year of swpping clutches, changing rear springs, and pinion angle till I fixed it. Most of mine was pinion angle adjustment. I added a 4 degree shim and it cured the problem. It drove me crazy. I mean I built mine with factory parts and changed nothing in tbe rear when cahnging to the four speed big block. Give that a try, it worked for me.
 
If you want, I can pm you my email. If you email me your phone number, I can call you and talk you through the multiple things I tried and discovered. Believe me i know the intense frustration due to his problem. People think you got to be kidding about how bad it shakes.
 
I just find it odd how by just changing the gear box would create an issue. Everything is physically the same size other then the gears inside the case. For now I'm going to leave it alone.I had gotten a good deal on the cast od 4 speed and figured worth a shot. 1st to 2nd was a big rpm drop that my 6 pack didn't care for. For now I'll let it turn the rpm at highway speed

Duster with my original 4 speed is smooth as glass no matter rpm,hill, speed, burnout or anything. Going to leave it in the car.

As for the shake it was like nothing I have ever had before.I own over 10 muscle cars ranging from t56,t5, 833 and muncie so not new to driving standard.. but this was undriveable.
 
If the gear box was the only thing you changed the last time I think it's pretty obvious the issue has to be in the OD gearbox. If you're using the OD bell and linkage with the standard 833 with no problems that's not the issue, same for the driveshaft. The problem has to be with the OD box.

Is the shake/chatter a 1st gear only problem?
 
The 3.09 low sends 16% more torque into the rear springs. I bet you a nickle your rear springs are bouncing. Put some clamps on them and try it again. Or put a big old wooden block between the snubber and the floor, for testing purposes.

But that is just a band-aid.
Your clutch does have issues, the 2.66 just masked it.
Your finger heights are very likely not the same.
 
I had the entire box apart and all the gears looked clean with no wear..The cluster pin is tight still since the box is cast. The leaf springs are brand new espo 6 leafs with around 500 miles..Brand new shocks as well.

The clutch is a mcleod performance diaphragm type with around 500 miles. I had looked at all the fingers today with it torqued down and all even to the eye.. There were zero hot spots in the new flywheel or pressure plate.

The chatter is not gear noise or gear rattle in the transmission..It reminded me of bad chatter of a extreme warped flywheel. It shook the car to the point it felt like it was gonna break something. This wasn't trying to launch the car or anything. Just trying to make the car move made it do it with low rpm or 3k steady and ride the clutch out. 2nd gear I could get it to move smooth but had to work clutch to get it moving. I can't see the springs bouncing trying to make the car move at 1500rpm riding the clutch. I could see doing a full wot pull from dead stop and getting wheel hop and chatter.

Why I come here and ask. Something I have never had happen.I have built 10 cars for myself all stick shift,number of customer cars and had quite a few 4 speeds apart with no issues. I built my own engines, transmission and set up my own 3rd members so have the experience.

I may try the od box in my 68 cuda to see if it does it in that car one of these rainy days. But right now I have to finish my 73 cuda and not going to put the time or effort into a 200 dollar od 4 speed.
 
You wouldna liked that od box anyway; the splits are outrageous for a hi-winder. It is a good box for a low-rpm,hi-torque engine. Something like a slanty or a stock teener. Or even a 2bbl 360. But if you got a revver, not so much.
That 3.09low likes 3.23s. or maybe 3.55s. 3.23s will get you 52mph @6400. And at the shift, the Rs will drop to 3460. Your engine got power there? Not much.The 1-2 powerband requirement thus is 6400 less 3460=2941!
Using the 2.66 box by comparison, the Rpm drop from 6400 is to 4595. The powerband requirement is thus 6400 less 4595= 1805; see what I mean?
2941/1805 = plus 63% more powerband requirement.
I tried that tranny. I even blew two of 'em up,before I threw in the towel.
I tell you what tho, if you put a GVOD behind one,and start splitting gears, you get 7 useable gears including double overdrive.
 
I did get to try it a few times doing a roll in 1st. Had to wind it uphigh then grab 2nd to make a good run. As you stated dropped a large amount of rpm. 3.09 to 1.67. My 6 pack is tuned right on with the 2.66 trans..Put it to the floor about breaks the tires loose as the 6 pack opens, grab 2nd and not one bit of hesitation for the outer carbs to come back on. That is before the 100-150shot of nitrous I use comes into play. Why I am leaving car alone now. Had to try it though
 
mischiefdart said:
I have an O/D in a 70 Dart behind a hopped up 318 and can't stand the 1-2 shift. Just got a standard box for it.
Click to expand...
There is one way to stand it; Make second gear in the OD box the same as second gear with the 2.66.
Say you liked second in the std box with 3.55s; then 1.91 x 3.55/1.67=4.06 rear gear.
So then you put a 4.10 back there, and shift at the same roadspeed with the od box as you did with the standard box .
Say you normally outshifted the 2.66low at 2800 at about 24 mph with those 3.55s, so you would be going into second at 24 mph, and you would be revving at 2022.
Now you outshift the od box at the same 24 mph, now at 3740rpm , and drop into second at, get ready for it,2022rpm. Second will take you to 65@5529(27s),with those 4.10s.
Cruising in od will be about 2417.
Cruising 65 with the 3.55s and direct 4th would be 2867rpm.
So, basically, with the od box, you trade away first gear into never-never land, to get 450 less cruising rpm.In the meantime the 2-3 split is pretty far out there too. Bad deal in my thinking.
I never liked it, until I started splitting gears. Cruising 80mph=2000 rpm in double od wasn't too bad.But the powerband requirement of just 1300 or so rpm, was amazing.
The ratios were;3.09-2.41-1.67-1.30-1.00-.78-.54 GVOD in red
The splits were......78....69....78....77....78....73
Now if you have a stock teener and outshift much earlier, now that is a whole new ballgame! But you'll still sound like a Mustang on the 1-2 shift when you start pushing it.
 
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From what I read the od bearing retainer is the only other part that was used only with od box. Remember that the throw out bearing slides on it..... and they do wear (could have a wear step at the engagement point) and can also bend. If could also have been loose on the od box.

I would have a close look at it.

My 2 cents
 
AJ/FormS said:
There is one way to stand it; Make second gear in the OD box the same as second gear with the 2.66.
Say you liked second in the std box with 3.55s; then 1.91 x 3.55/1.67=4.06 rear gear.
So then you put a 4.10 back there, and shift at the same roadspeed with the od box as you did with the standard box .
Say you normally outshifted the 2.66low at 2800 at about 24 mph with those 3.55s, so you would be going into second at 24 mph, and you would be revving at 2022.
Now you outshift the od box at the same 24 mph, now at 3740rpm , and drop into second at, get ready for it,2022rpm. Second will take you to 65@5529(27s),with those 4.10s.
Cruising in od will be about 2417.
Cruising 65 with the 3.55s and direct 4th would be 2867rpm.
So, basically, with the od box, you trade away first gear into never-never land, to get 450 less cruising rpm.In the meantime the 2-3 split is pretty far out there too. Bad deal in my thinking.
I never liked it, until I started splitting gears. Cruising 80mph=2000 rpm in double od wasn't too bad.But the powerband requirement of just 1300 or so rpm, was amazing.
The ratios were;3.09-2.41-1.67-1.30-1.00-.78-.54 GVOD in red
The splits were......78....69....78....77....78....73
Now if you have a stock teener and outshift much earlier, now that is a whole new ballgame! But you'll still sound like a Mustang on the 1-2 shift when you start pushing it.
Click to expand...
I just bought a 1970 A-body A833 out of a totaled 340 Duster for $250 that has been sitting for 20 plus years. I also have a scattershield I want to install. I will be selling the complete O/D set up when I get around to pulling it.
 
As I mentioned to racerkilla earlier on this post, my chatter was the same severity. A guy several miles away from me had the same issue when making a simple change. After a year of fighting mine, I talked to several people with odd chatter issues. One shop owner on this site changed a clutch and pressure plate on a Dart. Let it off the rack and couldn't pull out without shaking entire car. He changed clutches and everything same deal. He then put pinion angle shims in and it was fixed. The weird part was he just drove it in and serviced the car with new clutch and flywheel no other changes. The other guy down the street from me just clamped the front of his springs to compensate for the axle rotation. It worked, but shims would have completely solved it. Not sure why this happens, but it can and will. Lastly, springs are controversial now. Some metal in these springs are non ammerican metal and have been know to be weak. I ended up going with calvert because even mopar springs are made in mexico. It sounds rediculous, but again it fixed several members issues. My father was a Chrysler mechanic since the late 60s and could not believe that this so called chatter issue could be caused by the rear suspension.
 
racerkilla said:
I just find it odd how by just changing the gear box would create an issue. Everything is physically the same size other then the gears inside the case. For now I'm going to leave it alone.I had gotten a good deal on the cast od 4 speed and figured worth a shot. 1st to 2nd was a big rpm drop that my 6 pack didn't care for. For now I'll let it turn the rpm at highway speed

Duster with my original 4 speed is smooth as glass no matter rpm,hill, speed, burnout or anything. Going to leave it in the car.

As for the shake it was like nothing I have ever had before.I own over 10 muscle cars ranging from t56,t5, 833 and muncie so not new to driving standard.. but this was undriveable.
Click to expand...

Well, the OD transmission has a god bit lower 1st gear. IF the springs are weak, it might be pulling the pinion angle so far out that it's causing the chatter.


Just spitballin.
 
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