steep incline auto trans issue...?

[XJSuperman]

My friend is currently in Tennesee with his new to him '03.



He is running truck only (no hauling/towing at all).



They were on a steep (he says VERY steep) incline yesterday. Engine temp crept up to about 220-230*. Not too far from where he needed to be the transmission began to hunt hard for gears. He says he was under throttle the whole way up... which leads me to believe the convertor was not locked up (wasn't going very fast and I think he was in 2nd or drive). He went ahead and put it in 4 low and it stopped very soon after that and has been fine since then (no more steep grades) under normal driving. I test drove the truck for him and it seems to shift fine and he says it has shifted great the entire trip (before and after this one incident).



He plans to have the transmission serviced once he gets back next week... it's the only thing he couldn't get done before making his trip. Fluid levels are fine and fluid looks good.



Any thoughts?

 

[cerberusiam]

They freak out when the fluid temp gets that high. The gov pressure sensor and transducer don't like it.



I take no CEL or other lights and codes? Does he have a 48RE and will it lock in manual second? Best way to minimize temps.

 

[XJSuperman]

Yeah his is the 48RE. If memory serves my '04 when I had it would not lock the convertor until I was at approx 45 MPH... regardless of gear. I am guessing his is the same.



I think he just got it hot since it was perfectly fine before and after... but wanted to see if there is anything for him to do other than normally maintaining it. (and stay off that road LOL )



I also am thinking if this grade is as steep as he says he should have just put it in 4 low from the bottom and taken more time going up. It wasn't a through road by any means.

 

[WoodChuck]

I've never had mine that hot but I think I read something in the owners or service manual about hard shifting while hot. Make sure he knows if he selects manual second the converter will lock if he's going about 27 mph.

He should get the fluid changed asap especially if it's overdue.