Additive to fix Torqeflite shudder?

Rusty Muffler

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I think I know what the answer is going to be. As many of you know I have a shudder at 40mph cruise in 3rd gear only and read up on it and if could be a transmission problem. I then discovered a snake oil called Instant Shudder fixx Instant Shudder Fixx - Lubegard .

Has anyone tried this and is it safe on older torqueflite 3 speeds like is on my 57 Belvedere? It's worth 12 bucks as long as it doesn't damage my transmission.

I didn't want to go to the expense of changing all the transmission fluid only to not have it fix it.
 
When Chrysler first came out with lockup converters, they had the shudder problem. B&M used to recommend adding a little brake fluid. I've never done it, so I don't know.
 
I think I know what the answer is going to be. As many of you know I have a shudder at 40mph cruise in 3rd gear only and read up on it and if could be a transmission problem. I then discovered a snake oil called Instant Shudder fixx Instant Shudder Fixx - Lubegard .

Has anyone tried this and is it safe on older torqueflite 3 speeds like is on my 57 Belvedere? It's worth 12 bucks as long as it doesn't damage my transmission.

I didn't want to go to the expense of changing all the transmission fluid only to not have it fix it.
Exactly what trans is in your car? Is it a '57 torqueflite or something newer?

If it's an older (1957) trans, it's not going to have a lock-up convertor, and that snake oil is meant for lock-up convertors. So, I would say it's a waste of $12 and could possibly make things worse.
 
I somewhat dougt that product will fix your issue. It was designed to smooth the engagement of torque converter clutches when they would engage. Those torque converter clutches did not exist until the later 1970s.

Chrysler varied the lock-up speeds from the initial 27mph in 3rd gear up to 53mph by 1980 (on my '80 Newport 360 2bbl).

It would be unusual for any transmission to have a shudder well after the clutches were fully applied. A shudder after the clutches are fully applied would mean slippage is happening, it seems. Might check the lube pressures of the transmission. Shudders always happen upon initial engagement at the shift point.

The torque converter shudders happened when the clutch would engage, with a worn torque converter clutch. It could be made worse with more throttle and lessened with less throttle, at engagement.

LubeGuard has a similar product called "Shudder Fix", which is what the transmission shops usually recommend. LOTS of great reviews online. Check out the LubeGuard website.

Has anybody checked the angularity of the driveshaft at the rear axle, otherwise known as "pinion angle"? Are the rear springs sagged a bit to lower the rear body ride height?

Just some thoughts,
CBODY67
 
i used it in my 2015 z71 sierria with garbage motors going to “ eco” friendly fluids my trans did that it does stop the shuddering it does make shifting smoother. however i was told i needed to replace the trans (6500$) i choose to use this product until trans was worthless it prolonged my agony of a new trans for 1&1/2 years 36k miles still had to do a trans. end game it works
 
Exactly what trans is in your car? Is it a '57 torqueflite or something newer?

If it's an older (1957) trans, it's not going to have a lock-up convertor, and that snake oil is meant for lock-up convertors. So, I would say it's a waste of $12 and could possibly make things worse.
Yes, stock original Torqueflite. Thanks for the good info.
 
Two questions....how many miles on the trans?? And how is the motor tune ....i.e. miles/time since last major ignition and carb tune-up??
 
I somewhat dougt that product will fix your issue. It was designed to smooth the engagement of torque converter clutches when they would engage. Those torque converter clutches did not exist until the later 1970s.

Chrysler varied the lock-up speeds from the initial 27mph in 3rd gear up to 53mph by 1980 (on my '80 Newport 360 2bbl).

It would be unusual for any transmission to have a shudder well after the clutches were fully applied. A shudder after the clutches are fully applied would mean slippage is happening, it seems. Might check the lube pressures of the transmission. Shudders always happen upon initial engagement at the shift point.

The torque converter shudders happened when the clutch would engage, with a worn torque converter clutch. It could be made worse with more throttle and lessened with less throttle, at engagement.

LubeGuard has a similar product called "Shudder Fix", which is what the transmission shops usually recommend. LOTS of great reviews online. Check out the LubeGuard website.

Has anybody checked the angularity of the driveshaft at the rear axle, otherwise known as "pinion angle"? Are the rear springs sagged a bit to lower the rear body ride height?

Just some thoughts,
CBODY67
No, but the car does sit level if that means anything? We jacked the rear wheels off the ground and "drove" it to reproduce this vibration at 40mph or about 1550rpm in 3rd gear. We didn't seem to get the vibration when locked in 2nd gear at the same rpm. We took the rear wheels off to see a change and didn't so it's not the wheels. To have a vibration or "shudder" it seems to me it would take something big enough spinning to cause this no? Like the torque converter. Also, it's not a continuous vibration, it's in and out about every 5 seconds.
 
Based on post #9 above, i would say the fact that it happens without the load of pushing the car is a clue....you are chasing a vibration from something spinning out of balance as you said.
 
Two questions....how many miles on the trans?? And how is the motor tune ....i.e. miles/time since last major ignition and carb tune-up??
As you can read in posts about a year ago, the engine was supposedly rebuilt by a backyard mechanic. No other info available. I looked it over and everything inside was beautifully clean with new gaskets, etc. I bought the car with it out and I installed it. She runs very smooth except for an erratic miss under load. Rebuilt carb, plugs, wires, protonix pointless ignition. You can't even feel it while driving. It's 301 V8 compression averages at 100psi after 1500 mile which I know is on the low side. So on this forum we've been through the gauntlet on the motor so now I'm looking at the transmission. This is an extremely original car and I believe the trans to have what's on the odometer, 74k miles.
I never completely replaced the trans fluid, just what was missing in the torque converter. The fluid looks clear but I should obviously replace it all. I just wanted to confirm that it might be the vibration.
 
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I'd look at the driveshaft and u-joints. Maybe the trans mount.

I'm not really good at figuring out transmission problems, but it would surprise me if the problem is in the trans.
Trans mount I replaced. I've grabbed onto the drive shaft and tried to feel any looseness and can't. Front trunion boot is in great shape.
 
No, but the car does sit level if that means anything? We jacked the rear wheels off the ground and "drove" it to reproduce this vibration at 40mph or about 1550rpm in 3rd gear. We didn't seem to get the vibration when locked in 2nd gear at the same rpm. We took the rear wheels off to see a change and didn't so it's not the wheels. To have a vibration or "shudder" it seems to me it would take something big enough spinning to cause this no? Like the torque converter. Also, it's not a continuous vibration, it's in and out about every 5 seconds.
Also, can fell the vibration in the steering wheel too with the rear wheels off the ground!
 
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