I was on my way home today and we have to go over a mountain pass. on the way up it my O/D OFF light came on and i didnt press the button. so i pushed it multiple times to turn O/D OFF light off and the light stayed on. so i figured id worry about it later, but as we were close to the summit my TRANS FLUID HIGH TEMP light came on, since i was close to the summit i drove to the top and stopped about 100yds. i turned off my truck and inspected to make sure there wasnt a leak or anything, which there wasnt. i started the truck up and only the O/D OFF light was on. i checked the tranny fluid and it was full and didnt smell burnt. So i decided to continue home, anouther 45 miles. when i reached the bottom of the pass and was able to get up to speed again the O/D OFF light turned off on its own and neither light came back on since. I didnt experience any shifting problems or anything and never had this happen before. What could have caused this? the last thing i want is to have the tranny go bad so any help would be great.

 

so do you normally drive the hill and if so was it a different temp. umm humid. it could've just been random

 

That's what happens when the transmission overheats. It's a darn good time to jerk that check valve out of the cooling line that goes to the radiator, and do a full ATF change too. The check valve delete is the subject of a DIY in the FAQ section of the forum.

Don't pull long grades in overdrive. It's a no-no.

If you'd had this problem a few years ago I'd have gladly driven down from Meeker to help out. :-)

 

ive driven it acouple times now and never had a problem. The outside temp today was a balmy 40 degrees. just to give you an idea of the road it rises over 2000 feet in elevation in less than 5 miles and is full of switchbacks and its the same on the down side.

 

i wasnt pulling anything or have of load of anykind, when i go over the pass should i turn o/d off or does it matter if im not hauling anything. i know that i shouldnt use overdrive when iim hauling. i had seen something about that check valve thing and was planning on doing it this sping when i did the tranny service. i have heard about the external filter is that any good or should i not worry about it or what about doing the shift kit? I want to keep this thing running for anouther 100,000 miles.

 

I believe that it should be de rigeur to install a remote transmission filter and a pan drain plug whenever you have an excuse to drop the pan. After that you need never drop the pan again -- just change the remote filter every 30,000 miles and the ATF every 60,000. With the external filter the internal filter will never plug because the external will catch everything before it gets to the pan. And as a nice little bonus the filter provides an anti-drainback valve to perform the same function as the notoriously sticky factory check valve.

While you've got the pan off, adjust the bands and install a new internal filter.

If you install a remote filter, just plumb it in where the check valve came out as that's between the transmission and radiator as the fluid flows so friction material (and most of the varnish if you overheat it again) won't get to the heat exchanger to plug it up. Whether or not you'll get another 100k out of the transmission with a remote filter is debatable, but if you don't install one and get rid of that check valve you'd have to be extremely lucky to make it that far. Most 46RE's give up the ghost between 140k and 180k according to our MIA resident transmission guru, MonteC. I replaced mine at just shy of 100k because I wasn't willing to wait for the slippage during upshifts into overdrive to get worse and send all of that friction material circulating around in the fluid.

A shift kit (heavy duty, not street/strip) might be a good idea, or it might not. If the transmission is sound it'd be a pretty good idea, but if it's got parts that are just looking for an excuse to fail it'll just give them that excuse. Should you choose to go that route, you'll probably want to replace the solenoids and install some beefier band anchors (that you can get from PATC as their "Power Wedge") just to be on the safe side. The 46RE likes to eat those parts.

Always switch off overdrive whenever there's a load on the engine, even if the bed's empty. Our stock transmissions just aren't as strong as they should be.

2000' in five miles... Douglas Pass Road (139) out of Junction? That's definitely a direct drive road once you start up the hill.

 

yeah i was talking about douglas pass, i didnt figure anyone would know so thats why i posted it the way i did. its good to see someone who was from the area. im fairly new to this area. so where can i get one of these external filter kits at? my tranny seems pretty strong yet but maybe ill hold off on the shift kit for now, but i was thinking of adding an external tranny cooler just to help to keep it a little cooler or is that a was of money if i dont tow or haul?

 

If you don't do heavy duty applications, the aux trans cooler is STILL a worthwhile investment. Spending a bit more, and getting one that is thermostatically controlled may not be such a bad idea. (so you don't overcool your fluid.) A trans temp gauge wouldn't be a bad plan either.

Most parts stores will carry everything. Or, check the usual online suspects. Summit Racing. Jegs. Etc.

 

Think guys ill have to do so shopping and get everything.

 

There are a couple of guys from Junction or thereabouts wandering around here somewhere, and I'm missing the Western Slope something fierce myself. There's nothing wrong with the way you wrote it, not at all. It just got me to thinking that it just about had to be Douglas Pass, being near Rangely and also during the holiday shopping season. And the thought of going over that hill in overdrive just make me cringe.

There were quite a few deep fried transmissions happening when the energy extraction folks from the flatlands started showing up in the area a few years ago. And lots and lots of wrecks, too, between the critters and the winter roads and a great number of drivers who had no experience dealing with either.

Right up until the energy extraction boom I swore that it'd take dynamite to get my *** off of the mountain, but after a few years of the boom I couldn't wait to get away from it.

Are you there for work or for college?

They're common as dirt, really. In addition to HeyYou's good advice, you can order the parts online from PATC.

If you're going to be doing a lot of out of town driving so you'll be going up and down the mountain a lot you might want to install a deep transmission pan, too. The same energy being dissipated in a greater quantity of fluid means lower internal temperatures and greater transmission lifespan.

I kinda hate to recommend throwing so much stuff at the problem because it's easy enough to spend about half the value of the (stock) transmission on all the parts, but on the other hand smoking off an automatic transmission is no fun and these trucks have a tendency to do just that.

It'd be a good investment (as HeyYou said), but be sure to install a bypass valve for cold weather. The rule of thumb is to shoot for 150-180 degrees in the pan, and about 30 degrees higher on the hot side (going out to the cooling system). Too cold is not quite as bad as too hot, but it's still not good.