Dreaded clunk when turning

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gdizzle

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66 dart, sedan, L6 with the stock suspension and axle and differential. 7.25
Everything been going fine, until yesterday , whenever I turn to the Left, there is a loud clunk in the right rear, and feels like a little jerk as well.
It is pretty loud. Doesn't happen when driving straight, no grinding. Only on the turn.
I bounced the rear end up and down, but makes no sound.
The shocks are only a few years old. How do i diagnose it? Thanks guys.
 
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Transmission mount.
You need to get it on a lift and give it a thorough inspection.
Doubt its a limited slip rear axle unless you installed it.usually a 7.25 rear is used behind /6
 
66 dart, sedan, L6 with the stock suspension and axle and differential. sure grip I believe.
Everything been going fine, until yesterday , whenever I turn to the Left, there is a loud clunk in the right rear, and feels like a little jerk as well.
It is pretty loud. Doesn't happen when driving straight, no grinding. Only on the turn.
I bounced the rear end up and down, but makes no sound.
The shocks are only a few years old. How do i diagnose it? Thanks guys.
I recently had that happen when I installed a new Sure Grip in my 8 3/4.
It just needed a little drive time, the clutches are tight and needed some break in time.
 
I recently had that happen when I installed a new Sure Grip in my 8 3/4.
It just needed a little drive time, the clutches are tight and needed some break in time.
That’s right it is not sure grip it is the 7 1/4
 
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I think it's time to inspect the Rear U-joint and if that's ok then pop the cover and check the spiders, the cross-pin and the axle splines.
When turning, the outside wheel has to travel a bigger circle.... and that means it has to rotate faster than the inside wheel, ...... and that means a lot of the engine torque is going thru the now-spinning spiders. In the straight-ahead position, they are mostly stationary.
It is odd that it only does it on the left side, so I suppose it could be a wheel-bearing, or even a loose spring mount, or even loose wheel-nuts.
But you'll figure it out in a jiffy.
Tooljunkie could be right too, and since that is the easiest test,(Well except for loose lugnuts), you might as well start there.
 
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7.25 had a SG option so i'd not bet big money it was a one legger . Id check spiders with the cover off. Easy to turn up on stands and with the driveshaft disconnected. AJ has good advice on right wheel turning on the spiders in a left hand turn.
 
Ok on a whim, jacked it up spun the wheels and I feel it get stuck, wheels are spinning opposite each other, so not sure grip. Pop off the cover and yep, missing tooth up there on the small gear (is that small pinion?) anyhow the big gear coming from transmission appears fine, then the medium gear for left wheel and the one for right wheel look fine, but the smaller gears are shot. One looks to be missing 2 teeth which is where the clunk came from. Some shavings and parts of tooth in the oil. So now what? Is this junkyard time? Or can I replace that gear with the differential in/on the car.?? I have the manual but I am not real sure what the parts are all called. and bunch of detail about washers and certain spacing etc???? Any help or guidance is greatly appreciated. Hope to do this with my son, . People fix this sorta thing right? Or do they just go buy a replacement pumpkin?
diff - 1.jpeg
 
Ok on a whim, jacked it up spun the wheels and I feel it get stuck, wheels are spinning opposite each other, so not sure grip. Pop off the cover and yep, missing tooth up there on the small gear (is that small pinion?) anyhow the big gear coming from transmission appears fine, then the medium gear for left wheel and the one for right wheel look fine, but the smaller gears are shot. One looks to be missing 2 teeth which is where the clunk came from. Some shavings and parts of tooth in the oil. So now what? Is this junkyard time? Or can I replace that gear with the differential in/on the car.?? I have the manual but I am not real sure what the parts are all called. and bunch of detail about washers and certain spacing etc???? Any help or guidance is greatly appreciated. Hope to do this with my son, . People fix this sorta thing right? Or do they just go buy a replacement pumpkin?View attachment 1715475985
No doubt you have a problem
When you have that much damage and all that metal bouncing around inside the differential you will need to tear down the complete assembly and do a thorough inspection before you determine which parts a ok to use.
Get your credit card out, this is going to be expensive.
 
Ok on a whim, jacked it up spun the wheels and I feel it get stuck, wheels are spinning opposite each other, so not sure grip. Pop off the cover and yep, missing tooth up there on the small gear (is that small pinion?) anyhow the big gear coming from transmission appears fine, then the medium gear for left wheel and the one for right wheel look fine, but the smaller gears are shot. One looks to be missing 2 teeth which is where the clunk came from. Some shavings and parts of tooth in the oil. So now what? Is this junkyard time? Or can I replace that gear with the differential in/on the car.?? I have the manual but I am not real sure what the parts are all called. and bunch of detail about washers and certain spacing etc???? Any help or guidance is greatly appreciated. Hope to do this with my son, . People fix this sorta thing right? Or do they just go buy a replacement pumpkin?View attachment 1715475985

Yes you can fix that one with the differential rebuild kit, 2 new spider gears and the 2 side gears, the cross pin and the gear shim washers.

There was just a guy posted on here today with the part numbers and the supplier for the diff kit for the 7 1/4 rear end. His was a 1970, 7 1/4 that he was able to find the new parts for.
 
Ok on a whim, jacked it up spun the wheels and I feel it get stuck, wheels are spinning opposite each other, so not sure grip. Pop off the cover and yep, missing tooth up there on the small gear (is that small pinion?) anyhow the big gear coming from transmission appears fine, then the medium gear for left wheel and the one for right wheel look fine, but the smaller gears are shot. One looks to be missing 2 teeth which is where the clunk came from. Some shavings and parts of tooth in the oil. So now what? Is this junkyard time? Or can I replace that gear with the differential in/on the car.?? I have the manual but I am not real sure what the parts are all called. and bunch of detail about washers and certain spacing etc???? Any help or guidance is greatly appreciated. Hope to do this with my son, . People fix this sorta thing right? Or do they just go buy a replacement pumpkin?View attachment 1715475985

Check out the forum Transmission and Drive Train.
Remove axle from Duster
Remove Spider Gears
7 1/4 rear axle stuff
Post number 7
Has diff kit part numbers there.
 
Best bet is just to find another 7.25 rear. Your carrier is bad, can be replaced but your bearings are now contaminated with pretty hard material from the spider gears. It can be saves but must be flushed out and spiders replaced.

Here is requested Post #7

"...For all to know- MOTIVE premium open spider gear set for Chrysler 7.25 w/25 spline axles & 9"cover- part #C7.25BI- DID fit my rear end casting #2970051. Haven't driven it yet but everything was a perfect fit. You must use the axle remover which is like a huge dent remover- rented from O'Reilly's. Just wanted to be sure I posted this in case some are running the weaker 7.25 rear end. Thanks for all the help. Joel The seller was "drivetrainlasvegas"on Ebay...."

Sometimes you can pull these axles using a tire and rim and running the nuts until they are almost off. Then pull on the tire sharply and the slide action to the lug nuts will shock the axles to pop out. May take a few times. If it were a 8.75, I would have everything you needed minus the carrier in the mail tomorrow from a 1 legger core I got in the garage.
 
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Great info that's so much. I ordered the Motive kit on Amazon for $80. Now in the manual it talks about race and bearings on the axle shafts. Are those able to be reused or am I going to need to replace all that as well? I am hoping all I do is rent the axle puller, pop out the shafts, replace the spiders, then push it all back in?
 
Another question, how do you go about flushing out the differential with it on the car and jacked up?? I waved a magnet in there and tried to get the shavings, but is there a better way to flush it all out?? I have an air compressor.
 
Brake cleaner and rags. 5 cans. Well ventilated area and a catch pan under diff. Once you have rinsed all the oil out the filings are easier to get out with a magnet and compressed air.
I prefer to pull the carrier out so i can get at pinion area better to clean it. But it will require setup if you pull it. i have my 8.25 gutted right now and cleaned it up. Was just dirty though.
 
Diesel fuel, I put the diesel fuel in an under coating spray gun and put a 3' long piece of clear plastic hose on it.

Then you can reach in from the outer axle opening and wash everything into the center pumpkin area, then mop it out with some terry cloth towels.

Can spray up into the ring and pinion bearings and the front nose cone while turning the gears to wash out the bearings and races. This will drain into the botton of the pumpkin too.

Biggest thing is to wash out the bearings as best you can. Those ring and pinion gears are so hard they can handle any of the small debris that can't get wiped out.

Assemble the unit with new gear lube then change the gear lube right away again within the first 200 miles.

Good to Go
 
Another question, how do you go about flushing out the differential with it on the car and jacked up?? I waved a magnet in there and tried to get the shavings, but is there a better way to flush it all out?? I have an air compressor.
I drilled and taped a drain hole in the housing to help get all the crap out and preform regular maintenance.
With the axles out I use a broom handle to push rags soaked with brake cleaner down the axle tubes.
 
Ok i was able to leave the brakes connected and on . Once i undid the 4 screws the shaft just slid out. So do i do bearing grease on outside of race when i reinstall it?
B2A59720-2CE6-4C4E-91D4-C8FC6E52BA41.jpeg
 
OK I see a bearing seal there in the end of the tube on that 7 1/4 rear axle.

I am thinking there is a roller bearing just inside that seal. You need to reach in through the seal feel if that roller bearing has grease on it or if it gets lubed from the gear lube coming from the pumpkin.

Thinking it is gear lubed on the 7 1/4s.

The 8 3/4s are grease packed on those.

If it is gear lube just pour a little more lube in through the seal on to the roller bearing. Then stick the axle back in.
 
OK I see a bearing seal there in the end of the tube on that 7 1/4 rear axle.

I am thinking there is a roller bearing just inside that seal. You need to reach in through the seal feel if that roller bearing has grease on it or if it gets lubed from the gear lube coming from the pumpkin.

Thinking it is gear lubed on the 7 1/4s.

The 8 3/4s are grease packed on those.

If it is gear lube just pour a little more lube in through the seal on to the roller bearing. Then stick the axle back in.

Not for sure here ^^^^
You may have a sealed bearing on the axle, if so just make sure it spins freely. then reassemble. You don't want to put grease on that area outside of the the seal cause it can work out on to your brake linings.
 
Ok i was able to leave the brakes connected and on . Once i undid the 4 screws the shaft just slid out. So do i do bearing grease on outside of race when i reinstall it?View attachment 1715479308
Should be a sealed bearing just rub a little lube on the lip of the seal. To much grease out their and your going to be attracting dirt.

upload_2020-2-29_23-2-42.jpeg
 
View attachment 1715479353 Here is pic of the shaft. Bearing seems fine. Maybe just thin film on the outer race, View attachment 1715479353
Wipe it off real good but dont spray it. Install dry with lube on the seal lip. You can spray the seal with brake cleaner to clean it up. Also put a light on the other end or in the middle of the housing to look for any debris in the tubes.
 
084E8DE3-BD9C-4B50-A178-1505716D0E5D.jpeg
Ok emergency. I am now looking to remove the pin that holds the spiders and there is no bolt holding it in? And one end is slotted? Does this have to be driven out? Can that be done with it on the car?? This is not how it looks in manual.
084E8DE3-BD9C-4B50-A178-1505716D0E5D.jpeg
 
9DC48AE8-D4E2-4967-9408-0EA78B952F8C.jpeg
And there it is, rotated and there is a roll pin, there is no way to pish it out. So what do i do? Drill it out? Then need to find a new one? Uggg help.
 
If I remember right, I think there is a roll pin that needs to be driven out on that main center spider gear pin. Have to use a drift punch to get it started.

I may have used a 3/16 drill bit to drive that roll pin out because of the close fit.

Your new diff kit should have a new roll pin in it, look over your new parts.

Here is the tricky part, the large pin will slide easy when you get the roll pin out. But it slides up to one tooth on the ring gear.

So here is your choice, stuff a bunch rags in around the pumpkin gears to keep them protected, then take a die grinder/cut off wheel and grind a little bit off of that one ring gear tooth to gain clearance for the pin to come out. Polish a taper on that tooth so it does not wear the pinion gear when done.

I have done this ^^^.

Otherwise you have to pull the differential housing out to get the ringear and diff housing out, then you remove the ring gear on the bench, then the diff pin will slide right out. Lots more work . . .

It has been a while since I have been into one of these 7 1/4s, so see what you can figure out. Maybe you can find an expolded parts veiw of what you have.

Once in a while you will get into a rear end that has a small hex head bolt holding hat diff pin in, sometimes that hex head will have sheered off. See what you can figure out.

Good Luck
 
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