Reading trans temp on 1st gen

That doesn't really change the issue of gearing, that just means you may have made whatever issue you already had worse by getting the bigger tires.

As I said in my first post, I've never heard of anyone cooking their trans because they went to 33's. That doesn't mean that you can't fry your trans if already have an undiagnosed issue, then move up to 33's. That might push you over the edge. Although a lot of people post questions about how underpowered their 4cyl is fearing something is wrong, but it turns out it's just a 4cyl, lol.

It definitely wouldn't hurt to install a temp sensor, just to see what it's doing. Proper gearing will help, too. There are a bunch of websites out there (one is like grimjeeper or something) where you can enter your info (engine, trans, axle gears, tire diameter, etc...) and it will spit out what your rpms should be. Then you can play around with alternate gear ratios to get it back to (at least close) what it should be with stock tires/gears.

To answer your OP, though, the trans temp does usually hover pretty close to the coolant temp, unless you have a trans cooler, then it's probably a dozen or more degrees cooler. I know I've had the trans temp in my 5th gen 4Runner up to around 230 (towing a 3800# trailer up a super steep hill), and that wasn't enough to get the dash light to turn on, and even when I felt the heat from the trans on my Tacoma towing a trailer up a hill (pre trans cooler), the light didn't come on either.

I only just recently figured out how to read the trans temp on my 04 through the OBDII port and my Torque Pro app so I have yet to get a good feel for the temps.

So I'd say get a trans cooler no matter what. They are easy to install, and are cheap insurance. Just run it in-line with the stock trans cooler in the radiator. They cost like $50 from E-trailer or other retailers.

 

I’ve got a scan gauge for my 2003 and input the x-code I saw somewhere but still have not been able to get it to read trans temps.

I also recently found out altitude has a huge effect on mileage, and not the one I initially would have expected. Driving around upstate NY with a mix of city and highway driving I usually get around 200-220 miles per tank. I can squeak out 250 but she’s bone dry. Recently went out west and I got my best MPG ever in CO. Even climbing mountains and sustained travel over 10k feet I was easily getting 300 miles per tank... I wonder if the weed they put in their gas out there chills the fuel consumption down

 

That’s what I thought too and then got my scan gauge to do trans temps.
Pleasantly surprised.
I’m going to regear at some point. I’m curious to see how much better heat will be.

 

Just from my short few drives around town with the new OBDII setup, the trans temps are 15 or so degrees cooler than the coolant temps. I'm still not quite sure which trans temp to trust since I was experimenting with different PIDs, then found a "stock" one on the Torque app, and of course they're all different, lol...

 

Weed in gas...lol

 

Well...shit.

 

Here's the thread:
https://www.tacomaworld.com/threads...ansmission-temperature-pid-for-torque.686658/

For me though, it's not about knowing what the actual trans temp is. It really doesn't matter if it's 10 degrees off. It's more about looking for changes when you don't expect a change.

 

yea i would like to monitor trans temp to prevent a issue.

 

Yeah, with your '96 you'll need an aftermarket one like that timmy the toolman video posted earlier.

Sorry to hijack your thread with talk of the later model ones with OBD compatibility...

 

yea ik the hijack lmao no worries. that trans temp cluster from timmy didnt look to hard so

 

Wow that sucks. I bet the wheel/tire weight is contributing a lot to the mpg loss.

I thin

No, I get around 280 per tank. I was referencing the guys who build their overlanding vehicle up so much they only get around 13 mpg.

 

ooooooooh okay, for a second i was thinkng, idk something might be wrong if your only getting 175. but ya, if your talking about being loaded down with OL gear. sense.

 

I get around 16-17 mpg mainly cause of my 4 banger always working harder to get up to speed maybe I’ll get better mpg with these 285s once rolling

 

my truck is doing the whole over landing, but it’s almost defeating the purpose since my range falls for every new item I add on.

 

By the time your trans light on the dash decides to illuminate , chances are you have done some damage to your transmission fluid . I dont know why Toyota engineers thought it was safe turning that light on close to 300 degrees . They certainly could have gave us earlier warnings from the idiot light .
1st gen , 2nd gen as well as 3rd gen all illuminate the idiot light on the dash way too late so do not rely on this to cool your transmission down .

An aftercooler and something to monitor transmission temps is a cheap alternative to cooking your freshly replaced fluid .
https://www.tacomaworld.com/threads...l-toyotas-write-up-with-many-pictures.526283/

 

I'd like to jump in with a couple of questions if anyone can offer their 2 cents.

I have the 3.4L auto running 4.10 gearing on 285/75/R16's. Side note: 3 inch lift.

I can cruise along quite happily on relatively flat highways at 1500-1600 rpm going 80-90k (that's 50-55 mph for you guys lol)
Mountain passes -which are common for me out here on the West coast - are a different story.

Question 1: What can I do to keep my Auto transmission happy during these uphill stretches - apart from buying aftermarket trans cooler?

My current method is to stick to the far right lane and try to stay in roughly the same gear - using the tach as my guide and/or by ear. I inevitably lose speed with this method.
​

Question 2: I read elsewhere that the early Tacoma ECU's don't send Trans Temp data to the OBD2, hence the limited success with the Ultragauge.

They only have the idiot light despite having from what I have researched, the same trans temp sensor part as the later ones. Is it not possible to tweak (re-wire?) our ECU's to send data to the OBD? I'm guessing it's more complicated than that. ​

 

I dont have an automatic but I have noticed on my ultragauge in my manual, that if I am trying to accelerate especially up a hill, from a low rpm, no matter the gear, it shows a bigger engine load% than if I keep the Rpms a above 2500. Also I will see the engine temps start to rise the longer I am trying to keep the same speed, at a low rpm But if I have the rpms up above 2500 while keeping pace uphill, the engine temps go down.
This has been confusing me as it seems counterintuitive.

 

Locking converter .
The converter is locked on flat surfaces
Climbing steep passes , the converter is mostly unlocked creating all kinds of additional heat

towing a light trailer with a vehicle not designed for towing, even an empty trailer causes the TCC to stay unlocked when driving on a slight incline. I have seen this happen more than once. The converter turns blue and the fluid turns clear. The customer brings the car in because the check trans light is on. $$$$$

http://www.autoshop101.com/forms/h16.pdf

 

I’ve noticed that my truck feels like it’s driving its strongest when I’m above 8,000 ft. Especially going over mountain passes when I’m pushing 11-12k-ft.
The tacos like to get high too

 

My Tacoma loves higher rpms