Transmission Whine and Indecisive Shifting

dash9 · #1 (**permalink**) 02-23-2008, 06:26 PM

I have a 2007 Tundra 5.7 with about 10,000 miles on it now. When I first got the truck I could barely hear the engine when it was running, much less the transmission. Now the transmission has a whining noise in all gears. It's not loud but enough to be annoying. Also, when I come to a yield sign and slow to about 10 mph to check for traffic and then attempt to accelerate through the turn, the engine revs to about 1500 rpm before it finally decides to pick a gear. The hesitation lasts a good 4 - 5 seconds and could be dangerous if oncoming traffic is fast. Has anyone else experienced these problems? I have had it back to my local dealer once after I first got the truck but they claim they could not find a problem. Thanks

Jerry/dash9

OTR · #2 (**permalink**) 02-23-2008, 06:32 PM

I get a whine in the transmission when it is not up to operating temp under hard acceleration. I usually let the engine warm up for a while in the AM and when I get on the on-ramp the tranny will whine a little. Truck has 27,000 miles and is a 6-spd. I don't experience the hesitation that you are.

Steffen10 · #3 (**permalink**) 02-23-2008, 06:35 PM

Mine has almost 12,000 miles on it and I haven't noticed a whine or any kind of hesitation when accelerating

slackjaw07 · #4 (**permalink**) 02-23-2008, 06:37 PM

I'm confused: You said that when you first got the truck you couldn't hear any thing abnormal. Then you go on to say you had it back to the dealer when you first got the truck.

If you are experiencing what you describe, it should be easy enough to have the dealer's service manager ride with you so you can duplicate it for him. If you don't trust your current dealer...find another one.

thumbster · #5 (**permalink**) 02-23-2008, 08:22 PM

My transmission only whines in 3rd and it's very subtle. I'm sure it has to do with the way the internal gears mesh together.

If you typically drive on the slower side and then suddenly romp on the gas and drive like Dale Earnhart, the ECM gets confused because it's being forced to do something out of character for the learned driver habits. Some lag is normal, but 4 seconds sounds a bit too long. No transmission is perfect in terms of it's shift behavior in all situations. Drive by wire doesn't help this either. My advice would be to disconnect the neg battery terminal for a while resetting the ECM. Then re-connect and drive the truck a little harder than normal.

RONE · #6 (**permalink**) 02-23-2008, 08:37 PM

I've found if I coast through a stop sign (at about 2mph), the transmission hasn't quite yet decided if it should downshift to 1st, or stay in 2nd. If I hit the gas at this point, the truck hesitates for about half a second, then takes off.

dash9 · #7 (**permalink**) 02-23-2008, 08:53 PM

Thanks everyone for your input. Sorry about the confusion on the dealer visit. I went to him about the hesitation. At that time I was not hearing anything from the transmission. I plan on trying again with them. The subtle whining can be the normal for the 6 spd. but the hesitation on changing gears on a slow corner is just too much to overlook. Some of the whine can also have come from my towing an open car trailer with my Cobra on it. Have taken some rather long trips with it back there so that could have caused it. Thanks again for all the input.

miketn · #8 (**permalink**) 03-19-2008, 08:39 PM

I just took my 2007 dc to Toyota for the same problem (seems like the trans is not sure what gear to go into when I'm coasting down a slight grade and then start to turn a corner, 1st or second?) They called me about an hour after I had left it and said they were going to replace the intire trans, it would take 5 days to get it and a day to install.

Toyota

sfz989 · #9 (**permalink**) 03-20-2008, 12:53 AM

I have experienced mine not finding a gear under hard acceleration then letting off and trying to ease back into it. I was able to tap the gas a few times before it actually picked a gear. It's done this to me twice so far, both under hard accel. Also does a weird little clunk when going up a slight incline and letting off the gas, almost like slack in the read end. It worrys me a little sometimes but then I just forget about it and keep on trucking. I will be taken it to the dealer before the warranty runs out for sure, or until something breaks

FL_Tundra · #10 (**permalink**) 03-20-2008, 07:27 AM

I have the 5.7 with the 6 speed also. The only time that I notice any transmission issues, is when it is cold. When I leave my house in the morning, I have to make a turn onto another street about a block away. When I slow down for the turn, then accelerate, the transmission seems to go into a false neutral for a couple of seconds. It can't seem to decide whether to upshift or downshift. Happens every morning regardless of ambient temperature. It also won't shift out of (I think) it is 3rd gear for about another block. After that, it is fine for the rest of the day. I have 8K miles on it now, and it has done this since new. No noises, just the delay. Has not gotten worse, so I just assume that this is normal for this transmission. I have the lifetime powertrain warranty from the dealer, so have not been too concerned about it.

dragaeran · #11 (**permalink**) 03-20-2008, 08:09 AM

I get a good deal of indecisive shifting and hesitation from mine...5.7 6spd, but I think it has allot to do with peddle finesse, not a real problem. I have mentioned before that the 5-15 mph zone does seem to be problematic for the new tranny and there is a lag between peddle and engagement. I sometimes get a lurching surge of power if I slam the gas when the truck is in this speed zone.
Take the advice above and reset the computer. Then you can drive a little more agressively for a few hundred miles and the system to learn the new shift and acceleration model.
Overall, I think the engine tranny mating is somewhat lacking. They set the first gear so low and I would assume 2nd is pretty tall considering the performance I am getting. I guess we just have to remember this systems focus was on tow/haul more than a performance truck---excuses? anyone? another excuse for them??

Sanosuke · #12 (**permalink**) 03-20-2008, 12:31 PM

Looks like a firmware update might have to be fleshed out to iron out the "indecisive shifting" in the transmission.

Sanosuke!

FIVEPOINTSEVEN · #13 (**permalink**) 03-20-2008, 12:39 PM

I agree with dragaeren on the pedal finesse for the 6spd with the 5.7...I can almost feel when it wants to shift and when it will downshift and if you play it right you won't have any problems. Its not a surprise to me when I'm slowing down to 5-10mph and it downshifts and I press the pedal and it wants to launch...This is to be expected when slowing down that the tranny will shift to 1st...Ours just happens to be a really short 1st and so you just have to feel it out...I think its pretty predictable what the tranny will do...You just hafta try and learn it and really feel the shifts and then you should be fine. I'd rather have it downshift to 1st also because I like the fact that I CAN take off from a stop light or do what I need to do FAST if need be.

TP121 · #14 (**permalink**) 03-20-2008, 12:44 PM

Quote:

Originally Posted by RONE

I've found if I coast through a stop sign (at about 2mph), the transmission hasn't quite yet decided if it should downshift to 1st, or stay in 2nd. If I hit the gas at this point, the truck hesitates for about half a second, then takes off.

x2 - but mine is a rolling stop...

I also find it more common when travelling downhill.

sim · #15 (**permalink**) 03-20-2008, 04:57 PM

I took mine to the dealer for just this issue - they removed about a pint of fluid (no idea how that was supposed to help ) - they had it for 2 days and couldn't reproduce -supposed talking with HQ - now I can't decide if its better or worse, but I can 'make it happen' when I want...

I agree its mostly a peddle finesse thing - but the reality is when I want to 'slam it' I need it to do the job and not hesitate - and its frikkin aggervating on the yeild/accelerate times as well.