Vibration in Overdrive (1 Viewer)

[Quazii]

Just bought an 88 FJ62. With the exception of an OME suspension (minimal to no lift ) it is stock. LT235/75R15 tires on stock rims.
Here's the situation. When I'm driving up a a hill sometimes it vibrates (the entire truck shudders). If I let off the gas it goes away but may return once I press the gas again. If I drop back to third it goes away (this is how I go up steeper hills). Other than this it shifts smoothly and doesn't slip. The fluid is full and I'm considering having it flushed. As far as I can tell only under load and in overdrive it has a bad vibration. Ideas

Thanks,
Chris

 

[M-80]

So nobody has run into a problem like this before? The previous owner said this started to her when she had the gear shifter changed out and it only happened a few times to her.

 

[Maxdaddy]

Same issue

Any resolution to this issue? I know its a dead thread but I'm having exact same issue. I took it to the 5th tranny shop I called(first 4 wouldnt touch an auto LC transmission) had them test drive it and he said he didn't know, but said I should get my timing and valves adjusted. So I'm getting that done at our local LC specialist(he doesn't work on auto trannies) It seems like a pretty specific problem though. I see 5 or 6 threads with this same issue, but none of them have a resolution or one that I could find. Anyone out there had the Vibrates only in overdrive under load issue? I'm at a loss and would like to find out the problem rather then just throwing a new tranny in there. I had the u joints checked already. I guess possibilities are the worn splines, torque converter, lock up thingy, don't see how it could be the driveshaft. Help me guys I'm out here with not much cruiser help. truck has 152k miles, and I serviced it and checked the fluids about 15k miles ago, also i have added a tranny cooler.

I know about the rodney flush and party trick(which sounds insane by the way) I'm gonna try the flush this weekend, but doubt that works. Seems more serious then that.

Ideas? Thoughts?

Thanks for the help,
Max

 

[NYNick]

Don't know about your issue, but I understand these trucks are very sensitive to proper transmission fluid level. Follow the FSM instructions carefully, and don't just put back in what you flush out, as it might be low to begin with.

Careful with the "cold" level mark and the "Hot" level marks.

Add, warm up(drive), check hot level, add, warm up(drive) check Hot level etc.

Took me 2 1/2 quarts more fluid AFTER I put back the amount that I flushed out to get it to the proper hash mark on the dipstick, and now she shifts like a dream.

I'll keep my fingers crossed.

 

[FJ62sasquatch]

Maxdaddy - I have this same problem! Most of the time the cruiser runs great, but like you said at ~50mph in higher gears.. the entire thing shakes... It's not like a grinding gears thing.. Its not as nasty of a sound.. its more like running over one of those road side strips that is there to wake up sleeping drivers... I'm hoping its not the torque converter... I heard thats $$$.. U-Joints is another option.. but you said you checked that.. I also have an Auto Tranny, and would love to know what you find out!

 

[Maxdaddy]

Yeah it's really weird. I see threads started like this talking about the issue but not to many saying how it was fixed. The transmission guy checked the fluid and said it didn't smell burnt and was at the correct level. I'm gonna do a flush this weekend. Do I drop the pan then do the flush with the pan off? Or drop it put it back on fill it up then do the flush then refill the repeat?

 

[FJ62sasquatch]

Yeah it's really weird. I see threads started like this talking about the issue but not to many saying how it was fixed. The transmission guy checked the fluid and said it didn't smell burnt and was at the correct level. I'm gonna do a flush this weekend. Do I drop the pan then do the flush with the pan off? Or drop it put it back on fill it up then do the flush then refill the repeat?

I have no idea how to do any of that... I wonder if there is a write up... I know your not supposed to do any sort of flush that puts pressure on your gaskets because they will fail that way.. or atleast I think I read that somewhere.. I know i did! but anyway I'll start searching for a rodney flush write up.. what is this mysterious party trick you speak off?

 

[Texas993]

Max, make sure that you get the filter gasket and the transmission pan gasket before you start! Maybe a drain plug washer too.

I have the parts to do the flush, just need to do it.

 

[FJ62sasquatch]

Yes! this is what I was saying... You need the gaskets!! haha

 

[FJ62sasquatch]

ARE YOU FRIGGIN CRAZY!?!?!?! WHAT THE HELL!!! A party trick is going ~25mph and then SLAMMING INTO REVERSE!?!?!?!?!?!?!?! AM I THE ONLY ONE WHO SEEMS TO THINK THIS IS A BAD IDEA??!?!?!?!?!!?

 

[Maxdaddy]

I know man it seems crazy to do that. Thanks for the parts heads up. I'll grab those tomorrow so I have them already before I start.

 

[NYNick]

Nope, I think its crazy too! But people do it, it seems to work, it's just not going to happen on my truck.

 

[FJ62sasquatch]

Nor is it happening on mine... Maybe when I'm put in front of the auto shop and my H55 is ready to put in... Maybe then... But certainly not now

 

[snowakii]

What you have is a slipping torque converter clutch. The clutch only locks up in 4th (unless you have one of Rodney's modified shift bodies). That's why putting it in third going up the hill makes it go away.

The torque converter clutch can no longer hold the added load of going up a hill. It will get worse and worse until 4th will only work with little or no load.

The lock-up clutch locks up somewhere around 55ish (I believe it may be 53). Below the lock-up speed in forth.. no vibes.. above lock-up speed and sufficient load... vibes.

You need a new torque converter.

 

[Maxdaddy]

What you have is a slipping torque converter clutch. The clutch only locks up in 4th (unless you have one of Rodney's modified shift bodies). That's why putting it in third going up the hill makes it go away.

The torque converter clutch can no longer hold the added load of going up a hill. It will get worse and worse until 4th will only work with little or no load.

The lock-up clutch locks up somewhere around 55ish (I believe it may be 53). Below the lock-up speed in forth.. no vibes.. above lock-up speed and sufficient load... vibes.

You need a new torque converter.

Ok so is putting in a torque converter something I could do? I have done the knuckles and all the tune up stuff as a reference to my mechanical knowledge. Is pulling the transmission difficult? Should I look for a new transmission? If not whats the best place to get a torque converter. I saw one on cruiserparts.net used for around 300. Or I think Rodney sells a beefed up one not sure on price. What's the smartest way to go about fixing this issue?

 

[snowakii]

How deep are your pockets?

To replace the torque converter you need to seperate the transmission from the engine. Once you've done that why not replace the tranny too? Oops, to replace the trany you will need to remove the transfer case from the tranny..... keeps going as far as you want it to go.

You can simply replace the torque converter, but like I said it does require pullig the tranny. Depending on your garage and tools available, you can do this from below with the engine still in the cruiser. If you've done the knuckles and paid attention to all the details you can do this, but all of the pieces are bigger andmuch heavier.. duh. Get a tranny jack and a helper. It's not ideal but the tranny and t-case will come off as one unit, which will give you access to the torque converter.

But after going through all that, the tranny going out may not be too far behind. If you want to keep the t-case you have you need to remove it from the tranny which requires opening up the t-case.... While that's open, why not rebuild it too?

Sooooo how much do you want to spend and how much work are you up for right now?

If you also have the issue of the drive-to-reverse slop, the tranny output shaft is on its way out... new tranny or rebuild.

I don't know what Rodney's trannies go for now, but they are built very well and give you the added benefit of torque converter lock-up in 3rd and as you said a stout torque converter.

 

[RockDoc]

ARE YOU FRIGGIN CRAZY!?!?!?! WHAT THE HELL!!! A party trick is going ~25mph and then SLAMMING INTO REVERSE!?!?!?!?!?!?!?! AM I THE ONLY ONE WHO SEEMS TO THINK THIS IS A BAD IDEA??!?!?!?!?!!?

If you put it in reverse, that would be a bad idea. Read the instructions again.

 

[orangefj45]

sounds to me liks you guys are experiencing a shudder when the converter goes into lockup. this is not uncommon and not something specific to the a440f. over time the clutch surface in the converter becomes glazed. then when the clutch ( lockup ) gets engaged under load, it can and will cause a shudder.
there are some products out there to help with this exact issue. the one i like to use ( and have been using for 15 years or more ) is made by a company called "lubeguard" and comes in a black bottle with a red lid. most better auto parts stores carry it. designed specifically to bring old fluid up to snuff as well as remove glazing from the friction materials in your transmission ( bands, friction discs and lockup clutch ).
do not confuse this with any type of "stop leak" or "shift improver" as these products are a lot more aggressive and the chemicals in them are strong enough to swell up your seals and sealing rings, helping to prevent leaks and boosting pressure in the transmission. these are a band-aid at best and i'd never put a drop of it in a transmission.

hth

georg @ valley hybrids

 

[orangefj45]

the "reverse party trick" will not fix this issue. it's a simple way to cause a vibration in the output shaft of the transmission which in turn ( hopefully ) will loosen up the governor and return the shifting to normal.

don't try this at home kids.


georg

 

[RockDoc]

the "reverse party trick" will not fix this issue. it's a simple way to cause a vibration in the output shaft of the transmission which in turn ( hopefully ) will loosen up the governor and return the shifting to normal.

don't try this at home kids.


georg

So, as someone who actually knows auto transmissions, would you put the park (not reverse) party trick in the category of bush league but may help if you have messed up shift points, or incredibly stupid and those who try it should be sterilized?

For the record, I've done it, and no nuns perished as a result. On your advice, I'll call my urologist and set up the appointment.