tranny question

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trudysduster

trudysduster

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Have a 727 in my Duster behind a 440. Had this rebuilt back in March I think. Have had no problems until last weekend. I have a quiver in the car when I start off. It lasts till about 25-30 MPH. Not a grind but a kind of quiver. It runs fine past that. I can only think it is in the tranny. Not much to go on here I know and I don't know much about a 727 but is there anything in there that could cause this. It has a 1 year warranty on it and I will probably take it back but would like to know what some of you guys think it may be before I go in and make an *** out of myself here. I plan on putting it up on jack stands tonight and pulling the inspection cover and bumping it around and make sure nothing is obviously wrong like bolts missing but I would think if that was the case it would do it all the time. So please give me some suggestions here on what it may be. It just started this the last 2 times I drove it. Thanks, Bill
 
OK Lance, I will do that tomorrow. I guess it puts a lot more strain on those components on take off than on normal operating speeds. It seems to be fine over about 35 MPH. That's what has me puzzled. It seems like if it was in the tranny it would also have some effect all the time. I would be more inclined to expect it to be the tranny mount. I have the spool type motor mounts. I just greased the u-joints the other day when I put the axle bearings back in and didn't noticed anything but will check all this out again tomorrow. Thanks
 
trudysduster said:
OK Lance, I will do that tomorrow. I guess it puts a lot more strain on those components on take off than on normal operating speeds. It seems to be fine over about 35 MPH. That's what has me puzzled. It seems like if it was in the tranny it would also have some effect all the time. I would be more inclined to expect it to be the tranny mount. I have the spool type motor mounts. I just greased the u-joints the other day when I put the axle bearings back in and didn't noticed anything but will check all this out again tomorrow. Thanks
Click to expand...

Bill , I would definitely rule out everything you can before yanking the transmission out. I have seen those spool mounts come apart, I just replaced one myself..... and a 727. you could even get the rear end up on jackstands and run it through the gears while someone looks for anything out of the ordinary. I would get a ratchet and wrench on every bolt you can reach.
 
Watch for driveline bind while it up in the air.
(make sure the rear end hasn't moved for some reason)

It could be mounts, but it could be a separated tire also, so watch for that while it's up.
Separated tires can wobble side to side, or up and down either one.
 
don't know what kind of rear end your running just wonder if the axle bearing are adjusted correctly?
 
Bill, this started just before I had the axle bearings replaced. 66coronet, I am running a 8.75 rearend that had been cut down and running Moser axles and bearings. There are no adjustments on them that I know of. They are pressed on and one piece. Lance, I ordered a new tranny mount tonight and it will be here tomorrow morning. I am going to go ahead and change that anyway. looking back on this little shiver, it seems like something could be moving a little until it gets up and running and it would seem like a tranny mount would be the best likely culprit but again I will check all this out tomorrow. It is up on jackstands now and I am going to look it over. It doesn't feel like a motor mount because I didn't feel any movement when I set the linelock did a small burnout but not to say there isn't anything wrong with them. I will check tire separation while it is up but that would seem to be a constant at any speed and get worse the faster it goes. I will let you guys know tomorrow what I find and go from there. I am also going to pull inspection cover and bump the engine over to see the convertor bolts. I really don't want to take the tranny out. Just didn't know if there was any component in the tranny itself that would cause a quiver in the low end of start up that would cause a quiver. thanks for all the possibilities. I still like the tranny mount the best though so far. I don't remember if I changed it since we built the car.
 
trudysduster said:
Have a 727 in my Duster behind a 440. Had this rebuilt back in March I think. Have had no problems until last weekend. I have a quiver in the car when I start off. It lasts till about 25-30 MPH. Not a grind but a kind of quiver. It runs fine past that. I can only think it is in the tranny. Not much to go on here I know and I don't know much about a 727 but is there anything in there that could cause this. It has a 1 year warranty on it and I will probably take it back but would like to know what some of you guys think it may be before I go in and make an *** out of myself here. I plan on putting it up on jack stands tonight and pulling the inspection cover and bumping it around and make sure nothing is obviously wrong like bolts missing but I would think if that was the case it would do it all the time. So please give me some suggestions here on what it may be. It just started this the last 2 times I drove it. Thanks, Bill
Click to expand...
i seem to have the same problem with my 65 barracuda. 904 trans. it seems to shake a little when accelerating in first gear up till about 2200 rpm then disappears. had my driveshaft balanced, no difference. took the trans out and had it inspected and new clutches installed while it was out. same thing. i am just thinking i will live with it, but it really does bother me thinking it may lead to a catostrophic road side adventure one day.
 
trudysduster said:
OK Lance, I will do that tomorrow. I guess it puts a lot more strain on those components on take off than on normal operating speeds. It seems to be fine over about 35 MPH. That's what has me puzzled. It seems like if it was in the tranny it would also have some effect all the time. I would be more inclined to expect it to be the tranny mount. I have the spool type motor mounts. I just greased the u-joints the other day when I put the axle bearings back in and didn't noticed anything but will check all this out again tomorrow. Thanks
Click to expand...

i was thinking, is this a cast crank 440? i know you say it just started, but if the converter is supposed to be weighted, i guess it could be possible you lost a weight? the cast crank converters use 2) 20 gram weights that are welded on by the drain plug. just a thought
 
I put a new Hughes convertor in it in March when I had the tranny done. 2800-3000 stall I believe. If I lost a weight, it should be in the inspection cover I would think. I am going to pull it first. But even with that, if a weight was off wouldn't it vibrate worse the faster I would go. As the RPM's increase I would think it would get worse. This is what has me baffled. After about 35 MPH or it shifts into the last gear it is fine. That tells me that something is moving on take off when the torque is applied. I may just order a new set of motor mounts, tranny mount and replace the u-joints and see what happens. I hate problems with my baby. I will get at it after breakfast. Thanks
 

Did some looking this morning and found the tranny mount to be tight. there is no movement on the tranny at all. rear u-joint seems to be tight, no movement but the front u-joint has movement. I moved it very slow and could see some movement where the joint sits in the yoke coming out of the tranny. May explain a small vibration I have but I am not sure it would explain a quiver on take off. But one thing that concerns me is the yoke coming out of the tranny. I took a pic of it and to me it looks like it is not far enough inside the tranny. Again, I know nothing much about trannies but it seems to me like it should be maybe another 1-1 1/2 inches in more. I know you have to have some play for movement but what do you guys think. Again this has been like this since I had the car together and it didn't quiver like this so I don't know. I am going to pull the drive shaft and replace the front joint today. I also noticed a small amount of movement in the yoke up in the tranny. very little. let me know what you guys think. Is the u-joint the quiver problem or just a small vibration problem. Going to move towards the front of the car.
 

Attachments

maybe I need a new yoke if the u-joint has some play where the joint sits in it and some movement inside the tranny. does anyone know off hand what yoke that is by looking at it.
 
what I like to do is , push the yoke in the tailshaft until it bottoms out , and then make sure it comes back out at least 1" before seating in the axle yoke to allow for suspension travel. I have ran them a lot further out before simply because I didn't want to have the driveshaft lengthened the 1 or 1 1/2 it should have been, without any vibration or ill-effects. there is going to some movement in that area, but the u joints should not be moving at all at the yoke. the out put shaft runs through a bearing race in the tailshaft , and then through the seal. is it about a foot and half long, so there will be some movement. perhaps you can PM Tracy (fishy6eight) and ask him what could cause a quiver inside the transmission, or if it is even possible. maybe the bands inside the transmission need to be adjusted, I don't know, im not a trans guy either. I had a decent vibration in my charger recently, but I also didn't have second gear, I changed the transmission and mount, and its all gone.

trudysduster said:
maybe I need a new yoke if the u-joint has some play where the joint sits in it and some movement inside the tranny. does anyone know off hand what yoke that is by looking at it.
Click to expand...

the 727 uses a 29 spline yoke , is it 727 specific.
your yoke looks to be really far out, it should be seated about another 1 1/2" in
 
trudysduster said:
Did some looking this morning and found the tranny mount to be tight. there is no movement on the tranny at all. rear u-joint seems to be tight, no movement but the front u-joint has movement. I moved it very slow and could see some movement where the joint sits in the yoke coming out of the tranny. May explain a small vibration I have but I am not sure it would explain a quiver on take off. But one thing that concerns me is the yoke coming out of the tranny. I took a pic of it and to me it looks like it is not far enough inside the tranny. Again, I know nothing much about trannies but it seems to me like it should be maybe another 1-1 1/2 inches in more. I know you have to have some play for movement but what do you guys think. Again this has been like this since I had the car together and it didn't quiver like this so I don't know. I am going to pull the drive shaft and replace the front joint today. I also noticed a small amount of movement in the yoke up in the tranny. very little. let me know what you guys think. Is the u-joint the quiver problem or just a small vibration problem. Going to move towards the front of the car.
Click to expand...


Definitely a worn U-joint could cause a vibration. The picture does look like the yoke isn't in deep enough. Did you have the rear end on jack stands or were the tires still on the ground when you took the picture. That being said when I was working at the salvage I have seen more than one length on the 727 yoke.
 
the jackstands are under the rearend. tires hanging down. I pulled the inspection cover and all looks good there. But something didn't set right with me so I went back and checked the tranny mount again. I think it is bad. I put a little more *** behind the upward push and I got movement. I got the floor jack and put under the tranny and slowly lifted and I have about 1/2-1 inch of movement in the tranny mount. So the new one is due here about noon. going to change that. I need to know what yoke that is and maybe look into a new one and put a new joint in up front. I am thinking that with the mount bad, that could be changing the pitch on the rear some. maybe with the bad joint and the pitch being off that could explain the slight vibration. I am also thinking that the mount bad and maybe a band adjustment would be causing the quiver. Do you happen to know which yoke this is. How many yokes are there for a 727. where do I go to find this out. Thanks,Bill
 
U-joint is causing your problem when under torque load (cross flexing out of position) and goes away when the load is gone. will get worse if not replaced.
The large gap from tail seal to yoke is normal, the factory seal had a dust boot on the end that was over 1 inch long.
Replace both the u-joints and check yoke to output shaft spline engagement.
 
trudysduster said:
the jackstands are under the rearend. tires hanging down. I pulled the inspection cover and all looks good there. But something didn't set right with me so I went back and checked the tranny mount again. I think it is bad. I put a little more *** behind the upward push and I got movement. I got the floor jack and put under the tranny and slowly lifted and I have about 1/2-1 inch of movement in the tranny mount. So the new one is due here about noon. going to change that. I need to know what yoke that is and maybe look into a new one and put a new joint in up front. I am thinking that with the mount bad, that could be changing the pitch on the rear some. maybe with the bad joint and the pitch being off that could explain the slight vibration. I am also thinking that the mount bad and maybe a band adjustment would be causing the quiver. Do you happen to know which yoke this is. How many yokes are there for a 727. where do I go to find this out. Thanks,Bill
Click to expand...


Bill, I don't remember all the details but here are a couple that I found on eBay. The first one is longer and is listed for a truck application.

[ame="http://www.ebay.com/itm/Transmission-Yoke-Trans-yoke-Dodge-727-7290-Series-/140337303650?pt=Motors_Car_Truck_Parts_Accessories&hash=item20acc15062&vxp=mtr"]Transmission Yoke Trans Yoke Dodge 727 7290 Series | eBay[/ame]

[ame="http://www.ebay.com/itm/Dart-Duster-Demon-Cuda-7260-Transmission-Slip-Yoke-727-4-speed-340-383-400-440-/380957492517?pt=Motors_Car_Truck_Parts_Accessories&hash=item58b2d60525&vxp=mtr"]Dart Duster Demon Cuda 7260 Transmission Slip Yoke 727 4 Speed 340 383 400 440 | eBay[/ame]
 
I am going to replace the tranny mount today. I have contacted a guy on here for a yoke. Might as well wait on the u-joint and do it the same time I replace the yoke. I can only assume that these are the problems. everything else looked good. The tires have no separation as they are fairly new. They checked out ok. When I get these replaced and if it still does it, I will have this up to the tranny place and see what he has to say. May also be a band adj. I will let him ride in it and tell me. thanks.
 
Bill, I think the first one is the one I have. I am going to go measure the caps on it. thanks.
 
I don't know which one it is. Mine measures 3 1/8 " outside to outside of the yoke with 2 " inside the yoke where the u joint goes. It does have 1 1/8" cap diameter though which both takes.
 
what the hell do I have. this yoke measures something different than either the 7260 or the 7290 yoke on Dennys website. here is what I have on mine. the inside measurement from side to side of the fingers is approx. 2". and the outside to outside measurements of the fingers is 3 1/4 ". The caps are 1 1/8 ". The driveshaft is still in the car because I am going to have to move the car out tonight but can anyone tell me what yoke this is. If I bought a 7260 or 7290 I guess they would have a joint for it wouldn't they.
 
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