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wich do you normaly drive in???????
 

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Under 45 I go with D. I've read on some other boards (www.moparchat.com) that there is a new theory that why the tranny's go out more than other trucks on the Ram's is cause people leave it in OD all the time when they are not cruising or towing. Going to give that a try. Kind of a pain to smash the little button on the dash, but oh well.
 

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If you tow anything, turn the OD off! It generates a lot of heat if left on while towing. I installed a tranny temp guage, and just driving over HWY17 with it on, the tranny can reach 250deg's (in traffic) with the OD off (button lit up) the tranny maintains around 180 to 190 deg's.
Later....
Troy
 

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I started driving around about 2 weeks ago on drive verses OD. I put that winch on the front of the truck and know I have more power when driving in town and I want to see if I will get better mileage. That is good to know about the temperature lowering on drive.. DDGETHS
 

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The lock-up converter generates heat (lot's of it) when it's not locked (in OD) When I push the button (turning off the OD) the action "locks" the converter (preventing slip, heat generation) keeps the tranny out of the OD gear. I was a little surprized at how much the tranny temp swings when I use the OD or not.
Some of this I learned the hard way, some from my mechanic friend and some from my trucks tech. manual.
Troy
 

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Ahh, the good ol' OD question. The theory is your transmision will last longer if you don't use OD for stop and go driving, and hauling. Your Gas mileage is gonna go down, but vs the wear and tear on the tranny, it is worth it. If you haul something and "forget" to turn your OD off, bad bad things happen. that is when the tranny decides to go tits up.
 

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When running in OD (dash light off), the gears inside the tranny are spinning, rotating the output shaft nearly half-again as fast as the input shaft.

That's what generates all the heat. Normally the torque-converter is locked-up in either gear.

But in 4th (OD), you are using torque to generate less torque and more speed, and getting a lot of heat as a result.

When you turn OD off (dash light on), the intput and output shafts spin at the same speed, and none of the planetary gears in the transmission rotate at all. Very little heat produced here.

Basically, if the tranny fluid gets over 175 degrees, it's lifetime starts dropping FAST.

At 250*, you should just do a flush/fill, as the fluid is practically dead. Lifetime is only like 5 minutes at that temp.

Scary, huh?

Tranny temp gauge is one of my very soon to make planned mods.
 

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OK, I'll ask the stupid question of the day.. Is there a temp kit for dodges and how hard is it to install? Thanks DDGETHS
 

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These are all "digitally-controlled" gauges:
http://www.nordskogperformance.com/d70050.html
http://www.nordskogperformance.com/m9007.html
http://www.nordskogperformance.com/b2507.html
Use this sending unit:
http://www.nordskogperformance.com/sending.html

This one is cheaper, but the warning areas on the gauge are a bit high:
<!-- BBCode u2 Start -->http://store.summitracing.com/default.asp?target=%2Fproduct%2Easp%3Fd%3D10%26s%3D118%26p%3D222%26searchtype%3Decat" TARGET="_blank<!-- BBCode u2 End -->

Shouldn't be too hard to install.

B&M has the most complete kit. I think Jason has one.

The Nordskog ones look like high quality.

ISSPRO is well talked-about by the Diesel folk for pyrometers, and they also make tranny temp gauges.
http://www.isspro.com/Guages/R9055.html

Install would be to drop the pan, drill a small hole, and install the sending unit into that. Then run the capilary tube or the wire(s) from the temp sending unit to the gauge, and isntall the gauge where you want it.

I'm going to put one on the a-pillar, but I need another gauge up there to fill the Autometer pod that I want to use. Just don't know what the gauge will be yet. Probably vacuum. I seem to already have the rest covered.

{edit by JasonB: fixed URL format}
_________________
Aaron Wood
<!-- BBCode u1 Start -->http://muddyram.pavementsucks.com" TARGET="_blank<!-- BBCode u1 End -->
<!-- BBCode u2 Start --><A HREF="http://www.pavementsucks.com/gallery/viewride.cgi?ride_id=8" TARGET="_blank">'00 Ram 1500 RC SB 360 V8, Auto
3" Rancho Perf. Lift, 315/75R16 Goodyear MTRs
Reunel Front Bumper</A><!-- BBCode u2 End -->
 

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the reason heat is generated is because the torque converter is slipping. without the lock-up you only get about 90% or so of the power through the converter. the slippage creates heat. think about this... rub your hands together - thats the slippage. now put your hands together and move them both together - thats the lock-up on the converter. notice the heat difference between the two. i dont think you 1500 guys have a trans cooler (stock anyways), but it would be a very wise investment to install one. the constant in and out of the OD gear will also wear the trans down fast. basically if you are doing slow speed driving or heavy loads, dont use the OD.
 

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ok... it's 9:00am and I already learned my "new" thing for the day. Luckily I've had my first cup of coffee already!
I thought OD in or out was simply a matter of basically a "4th" tranny gear/drive being available. I didn't realize that it also affected the lower gears as well, regarding temp or torque. I only disengaged OD when towing over the mountain passes here in Wa.
I didn't even realize how often it was going into OD until I put on my Dynomax exhaust. It hunts in and out of it a lot. I found myself going 40-42 in 35mph zones just to get it into OD instead of listening to it hunt.
Thanks you guys!!!
I guess I go OD out unless on the highway, AND install a tranny temp guage soon!
 

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I started to take it out of OD awhile back, but its hard to remember to do it everytime you start your truck. I can't go over about 45 mph with out OD without having high rpm's. We could all solve this problem and get manuals, like that 6-speed I want.
 

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Afetr readin all the posts here, and recollectin' a bit ol' Dd wonders if by leaving the OD off and watching his temp guage and tranny fluid carefully, he could get away with running 35 inch tires for a while until he could afford 2 grand for gears and a front air locker. Anyone care to expound? P.S> Auto meter's pod pack works good with trans temp and vacumn.
Dd
 

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seeing that I am on my 2nd Torque converter... I think I might try that "inverted OD" switch/relay

might also install a tranny temp gauge!

Gotta love these tech boards!
 

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I don't use overdrive unless I'm on the highway moving at a steady pace. The first thing I do when I start my truck is turn off the overdrive. I know alot of people who have burned up there transmission by letting it jump back and forth between overdrive and drive in traffic much less towing. Its not just Dodges that have this problem. The heat build up does alot of damage. Running your trans at 250 degrees because it is shifting constantly will break down the fluid and then everything else in the trans takes a beating. I also get my trans serviced every 20,000 miles. I have 73,000 miles on my truck.
 

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About the torque converter "slippage". The torque converter should be able to have slightly different speeds on either side of it without generating too much heat. It's just a pump that drives an impeller.

When it "locks", it engages a clutch, and it shouldn't slip at all then, if it does, time for a new one.

Most of the heat is just the friction of the helical gears rotating each other.

Go drive down the highway, pull off, and feel your rear differential cover. Warm. Not enough to burn, but warm.

There's not a lot of surfaces rubbing in there, so not a lot of heat, plus you have the air, and REALLY thick fluid to protect it.

Inside the tranny, things are different. In OD you've got 3-4 planetaries spinning, so like 6-8 points that gears mesh, all generating heat. And, since they are spinning the output faster than the input, they are under a great deal of stress, and generate more heat than they would if they were spinning the output slower. (I don't know the specifics of why, but I know people that do).

So the tranny fluid can get pretty hot, pretty fast.

Anyone with a HD kit (big alternator, etc) should have both a tranny cooler and a power-steering cooler.

The tranny cooler is between the Air conditioning radiator and the engine coolant radiator. It's kinda small and mounted low. Tends to leak, too.

Power steering radiator is tucked up behind the first or second cross-member, hard to spot unless you're deep under your truck for some reason.
 

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I replaced my stock tranny cooler with huge (biggest Derally had) cooler. The upper guage in my pillar mounted guages is my tranny temp. Lower one is motor oil temp.
As I mentioned above in an eariler post, the tranny temp will reach 250 deg in summer time commute driving over HWY17 (stop & go)with the OD on. With it off (light on) the tranny temp stays around 180-190deg's
I was initially concerned about this tranny temp, but I realized it's been like this before I started to measure it. I had no concerns then. According to my Trucks techinical manual, the tranny temp idiot light is set for 275deg's and it says that temps up to that are ok. (tranny is still working!) Temperatures above that warrant investigation, and tranny fluid change. Installing a tranny cooler is not hard at all.
 

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jprtroy, do you have any pics of your pillar mounted guages? i am about to install - just looking for a good location for the guage...
 
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