Tundra transmission shudder.

I surf here a lot so I thought I'd share my little DIY project. I bought my 13' Tundra DBL Cab 4.6 about 2 years ago w/ 89'000 on the clock. It developed a very intermittent shudder under light acceleration that progressively got worse. At 102'000 the shudder was pretty consistent and aggravating. I watched all the trans flush videos and it seemed pretty straight forward. Evidently Iv'e got an oddball trim level as I don't have the trans cooler nor do I have trans lines going to the radiator. Iv'e got a little hockey puck up there that must be some type of cooler/heat exchanger. It was a PITA removing the trans line as they are very short. Anywhoo, I did the flush and the removed fluid, it was toast as expected. I refilled with the Valvoline dex/merc and the shudder is completely gone, The truck is a pleasure to drive again.

 

Drain and fill, drive, drain and fill, drive, drain and fill. Not worse than the heat exchanger mess, because only a fraction of ATF gets it to the exchanger (the pressure is governed by plunger inside valve body), and much easier to do.

 

Since the Dex/Merc is used and assuming dex3 it will have to be changed out yearly or biennial since is is a conventional fluid.
Shudder can also be caused by burnt clutch lining in the torque converter or a worn TCC relay bore in valve body. A synthetic WS with higher viscosity is the AISIN WS fluid.

 

Valvoline datasheet says it has slippage additives (this is what stopped shudder). Also at 7.4 cSt@100 it is much more viscous than Toyota WS w/ 5.45 cSt @100. In fact it looks pretty much like older JWS-3309 / Toyota T-IV ATF. I would keep it.

 

Thanks for the added info. I just did a swap myself to Dex3 for the stronger holding capacity. I was only pointing out their could be other issues if the shudder returns. Also some of us were talking about Dex3 in the supercharger thread and didn't want confusion on fluid types for their transmission.

 

I used the port by the arrow to pump out old fluid, refill, repeat. After about 5 cycles of that procedure the fluid got red so I'm assuming I did it right? I'll take any input you got. Thanks