Stuttering / Shaking at 25mph- 28mph (1 Viewer)

[Sym]

When take off from being at a complete stop and theres a subtle hill to drive up, i experience some shaking as if its misfiring.
So far Ive changed the spark plugs, and change out the differential and transmission fluid.
The tough part is it doesn’t always happen so it’s hard to show the mechanic whats going on. Even the dealership has no answers for me (not really surprising).

Its a 2010 fj with 166k miles.

 

[iwashmycar]

Automatic?

Could be the notorious Stuttering Transmission problem.

Did you do a full trans flush? Not just a drain and fill.

Any codes?

Sounds driveline related given the torque you are placing on it with a hill. U-joints? All zerks greased well?

 

[BMThiker]

+1 for auto trans stuttering as the issue. Usually in 2nd gear around 20mph then perhaps again around 40mph. Even a passive flush - drain pan, clean screen, refill, will help with this issue.

 

[Sym]

Automatic?

Could be the notorious Stuttering Transmission problem.

Did you do a full trans flush? Not just a drain and fill.

Any codes?

Sounds driveline related given the torque you are placing on it with a hill. U-joints? All zerks greased well?

Yes its an automatic. I didnt do a full flush, just a drain and refill. There are no codes. I havent checked the u-joints or zerks yet. Ill try that next.
When im hitting the gas too hard it either doesn’t happen or its harder to notice.

 

[Sym]

+1 for auto trans stuttering as the issue. Usually in 2nd gear around 20mph then perhaps again around 40mph. Even a passive flush - drain pan, clean screen, refill, will help with this issue.

When i had the transmission drained the first time i felt like the issue had gone away for about 3 weeks. In my case it only happens at 20-25 mph, never at 40.

 

[iwashmycar]

When i had the transmission drained the first time i felt like the issue had gone away for about 3 weeks. In my case it only happens at 20-25 mph, never at 40.

A drain and fill is only about 4 of the 12 quarts of fluid the trans takes. You may use up to 16 quarts to flush it out nicely. You did help it out a little by introducing fresh fluid, but you really really need to have it fully flushed, where they hook it up to a machine and run the new fluid through. You can DIY but it take a lot of fluid, routing tubes into the trans fill, ect.

Spend the money, probably save the truck. Its worth a shot. Also make sure its the right fluid....any old ATF may not cut it. Needs to be the OE WS fluid from Toyota IMO.

Its the torque convertor slipping which is why you only really feel it under easy takeoff and the uphill. Taking off faster probably enables it to lock up decently quick and not studder. More evidence that I think its the studdering trans issue and likely not something else.

 

[1MOA]

Drop the pan and change the filter. A fluid swap is a waste of time.

 

[BMThiker]

That screen is cleanable, just like the pan is. I've never replaced the screen. Always just cleaned it real good with kerosene parts cleaner. Unless the screen is physically damaged, throwing out the screen because it has a fine silt on it is just silly.

 

[Sym]

A drain and fill is only about 4 of the 12 quarts of fluid the trans takes. You may use up to 16 quarts to flush it out nicely. You did help it out a little by introducing fresh fluid, but you really really need to have it fully flushed, where they hook it up to a machine and run the new fluid through. You can DIY but it take a lot of fluid, routing tubes into the trans fill, ect.

Spend the money, probably save the truck. Its worth a shot. Also make sure its the right fluid....any old ATF may not cut it. Needs to be the OE WS fluid from Toyota IMO.

Its the torque convertor slipping which is why you only really feel it under easy takeoff and the uphill. Taking off faster probably enables it to lock up decently quick and not studder. More evidence that I think its the studdering trans issue and likely not something else.

Mechanics freak out when i say trans flush.

 

[Sym]

Mechanics freak out when i say trans flush.

Ive ask three in my area and they told me something about debris being transported throughout the trans. These are strange times in the world of mechanics.

 

[BMThiker]

I've only done a power flush once in another vehicle that had about 90K on it and it absolutely ruined the transmission.

It's messier and you'll use more fluid, but a passive flush is the only way I will go. YMMV.

 

[iwashmycar]

Well if you are getting trans shudder and want to try and save it without putting in a new trans or torque convertor, then getting NEW fluid into it is the next best shot. Adding about 4 quarts to the 12+ other dirty quarts in the trans is only a very slight improvement. You can do it a bunch of times and hope, but it may or may not rid you of the shudder.