Slow shift from first to second intermittently hard shift first to second when accelerating fast

I have a 2006 tundra double cab 2wd, a year ago I blew up the diff doing donuts in the dunes and I just recently replaced it with a new one it was sitting in the same spot the entire time, I would turn it on bi weekly to keep the fluids circulating. After test driving it I noticed the shifting issue so now I don’t accelerate hard from first to second. How long do I have until it completely fails and would a drain and fill with Toyota world standard and a liter of the Lucas transmission fix help at all or just use straight world standard

 

Hard to say. I’ve always had the delayed 1st to 2nd shift issue for years but not the hard shift when accelerating. I’d still think it was a solenoid issue but I’m no expert. I’d be tempted to open it up and replace the solenoids myself but that isn’t a trivial task.

 

It has 160k I believe I did a flush around 90k but I treated the truck badly I was 19 when I bought it with 59k miles but now I’m mature and I’ve been babying in for the past 5 years should I try the drain and fill with the additive?

 

IDK, I’ve tried AutoRx for my tranny to try and fix the delayed shift and it did nothing. I couldn’t tell you about the Lucas stuff since I haven’t used it. I would definitely recommend another drain and fill if it hasn’t been done in a while.

 

I think I’m going to do that and hope for the best

 

From what I’m reading, Lucas is just a temporary fix and won’t work for major seal leaks so it’s not a cure all.

 

It’s not leaking… yet but I’ll try that and then the next step would be repairing it
Should I have it rebuilt at a transmission shop or swap it out with a used one that has warranty in case it fails or just get a remanufactured one

 

You need to do a drain and fill or full fluid swap, but you need to check the level properly. Use WS or amsoil fuel efficient atf, don’t bother with any additives

 

I’m afraid a full fluid flush I don’t know if it’ll react well to all that new fluid or is that only for cvt transmission?

 

Yeah, I missed the part on where it helps with stuck solenoids. I’d be inclined to goto a reputable transmission shop (no chain places) and price it out against a used one. You usually get a 1 year warranty with a rebuilt tranny and it’s got new instead of used parts.

 

I wouldn’t “flush” it, but a full fluid swap using the trans internal pump shouldn’t cause any harm. Lots of write ups, but the fluid level check is important since our shift boxes don’t have a dip stick

 

So should I have it diagnosed professionally if the fluid flush doesn’t help? I can definitely remove and replace the transmission myself I would just make sure to buy a tranny with warranty
I’m just seeing prices of 5-7k for a shop to rebuild my transmission I’d rather buy a new for 2k

 

Yeah I saw a video on a transmission drain and fill and how to set the truck into transmission temperature sense mode to add the right amount of fluid since they decided to remove the dipstick

 

That’s up to you. I think a diagnostic might be anywhere from free to a couple hundred bucks. I’m not sure if they do partial rebuilds or if it’s always complete. Might be worth investigating if they have any tools you don’t.

 

Does the 06 have a dip stick?

what does the fluid look like?

 

No dip stick, sealed transmission for '05-06.

I've always had a slow shift 1->2. So many others have reported this with the 5spd that I think I even put a note about it in the knowledge dump thread.

It tends to be more noticeable on my '06 when cold. Or if warm and I turn it off long enough for all fluids to settle.

But if you're worried, carry it in to a Toyota shop and have the transmission serviced (fluid flush + level check). Just don't take to a non-Toyota shop where they may use pressurized pump to push the fluid.

 

Wonder if it's anything like this? This is an earlier truck and my truck suffers the same problem.
If you put the shifter in "2" from a stop and let it shift into 2nd on its own does the shift feel smoother?

 

When cold I have a delayed 2-3 shift. This is the ECU trying to bring the trans fluid up to temp (ie: normal afaik).

 

I can second this, I would say my 05 has a slower shift from 1 to 2. However, it doesn't do it when accelerating heavy. Every other shift is quick and smooth, smoother than most newer cars I have driven. I have always just assumed the "slower" shift is normal for the 1-2 shift, its always consistent.

 

Our trucks and their personalities! For me, when cold, 1-2 shifts early and 2-3 shifts late.

OP, if it's not "slamming" into gear, you're probably ok, but do what others suggested and do a drain and fill. My condolences to your lack of a dip-stick.

 

You've got 4spd AT, Jordan and I have 5spd AT.

It's possible I've been unaware of the 1-2 shift if it's early, but there will be times when I turn out of my driveway and start to accelerate where the truck will climb up around 3k before finally upshifting when cold. It's always been that way.

 

Ah, valid point, but it's a similar situation. There are times where I hit around 3k before it shifts, too, and I also recall the 1-2 being late and 2-3 being early until after I did a couple drain & fills and changed the filter.

 

I feel like when mine is cold, it always shifts a little different, but feel like that's how any car is pulling out of the driveway. I have never worried about it, but have seen many choose to do drain and fills. At 165k miles, I doubt mine has ever been changed. Havent made up my mind if I will drain and fill eventually lol