Trans fluid question?

[Drock]

M1028, TH400,with Gear vendors OD, Banks Turbo. I'm having some issues with the truck over heating on the highway. I think I've got it narrowed down to the NON locking torque converter slipping and heating up the RAD. Is there a thicker fluid I could use, that would perhaps give me less converter slip?

 

[cucvrus]

Never heard of any.

 

[SPECIALTYLC]

You need the cooling system serviced. Themostat,fan, radiator or similar system is not working properly.

 

[MarcusOReallyus]

Don't even think about using a heavier fluid to reduce slippage.

As mentioned, service the cooling system. If that doesn't solve the problem, it might be because the overdrive is making your trans work harder. Consider adding an external trans cooler. Since your truck is overheating, break from conventional wisdom and put the trans cooler BEFORE the radiator cooler, to dump some heat out before it goes into your cooling system.

 

[Drock]

Thanks guy's, the cooling system seems to be working fine around town, and if I keep it under 70MPH on the highway. I serviced it just before winter, and even added some water wetter to it. I also already installed a large trans cooler. My suspicion is (like Marcus said), that the Gear vendors is working the trans too hard. These TH400's don't have locking torque converters so they slip. All this being said it stays much cooler now in the winter then it was in the summer. Also if I keep it under 55MPH my fuel mileage doubles, Sooo

 

[Bob H]

I don't see the trans causing the cooling system to overheat, if the tranny was putting out that much heat it would fail quickly.

 

[MarcusOReallyus]

I also already installed a large trans cooler.

Before or after the radiator trans cooler? If it's after, leave it there, and add another before the radiator cooler.

TAlso if I keep it under 55MPH my fuel mileage doubles, Sooo

So keep yer big foot out of it, ya lunk!

 

[Drock]

Before or after the radiator trans cooler? If it's after, leave it there, and add another before the radiator cooler. I ordered one of these last night from summithttp://www.summitracing.com/parts/der-14202... So well see if this helps at all. I'll have to check and see how I installed the first cooler, I'm pretty sure the instructions had me install it after the RAD cooler.




So keep yer big foot out of it, ya lunk!

HA! well that's just not an option for me

 

[Drock]

Well that didn't work like I meant it to. Here's the (Derale) deep, cooler trans pan I ordered from Summit http://www.summitracing.com/parts/der-14202

 

[rsh4364]

Good choice on trans.pan,I would add a trans temp gauge for sure.

 

[o1951]

Careful off-roading with that.
Remember to clean out tubes afterwards.

 

[cucvrus]

Just wondering how far below the skid plate / cross member that transmission pan is going to hang. I would not recommend it for off road in mud and rocks. The tubes will fill with mud and make a mess to clean. I had a trans temp gauge sending unit in a different pan on a 1979 K20 and it ended up torn off in high grass. I hooked it up several times. Eventually it just broke the stud off and I removed the wire and plugged the hole. It was on the truck when I bought it. When I was younger I wheeled things really hard and the Chevy's always held up the best for me. I had good Fords with 7.3 diesels in them and they always had A4OD issues when the mileage got higher. Mostly electronic. Ever think of putting electric fans on the front of the radiator/auxiliary transmission cooler? Do you off road this in mud? I was thinking the cooler line might be a good place to put the cooling unit to protect it from debris and protrusions. Just thinking out loud. But the pan is cool for street use not sold on the off road use. I seen trans pans with a heavy skid plate built into them. But that is not going to help you with heat dissipation. My new truck has a transmission temperature gauge. What is good transmission temperature?

 

[rsh4364]

That pan only holds 1qt.3oz more than our factory HD 400 pans,but 3 qts.8oz more if using standard th400 pan.It doesn't hang much lower than a HD th400 pan.The nice thing is it has drain plug and temp.sensor bung.175 to 225 degrees would be good.

 

[cucvrus]

Sounds about the same as the deep sump HMMWV trans pan. I have found these several times at the scrap yard when I go there. This scrap yard gets the scrap from a local military base. I also bought a couple from swap meets. They have a deeper sump and a drain plug. I am not so trusting to put a sending unit down there. Past experience not so good results. I learn from my experiences. The only time I ever see high transmission temperatures is on long hard pulls when pulling a loaded trailer. And it goes down instantly after the hill is crested. Works the same on a new truck with a factory trailering package.

 

[rsh4364]

If you want to add trans.temp gauge without putting sensor in pan you can add Auto Meter in line sensor manifold # 2287.

 

[Drock]

I just got the pan tonight, It's 4-3/8" deep which shouldn't hang down any lower then the trans crossmember, skid plate, or the oil pan for that matter. I don't do any real off roading in this truck it spends most of it's life on the highway. And if I do I'll just make sure to clean out the tubes just as I would the radiator anyway. It's actually a pretty stout piece, heavy gauge steel and the tubes make it really ridged. I'll take some pics when I get it installed.

 

[Chaski]

Nice!

How many miles are on your TH400?

 

[Drock]

I just hit 30000 with this truck

 

[rustystud]

It's your engine working harder with that overdrive. There will be a little more heat generated with the overdrive in the torque converter but most is really from the engine. Have you ever hand cranked a meat grinder ? When there is no load it turns really easy, but start adding meat and then it gets harder to keep the same speed up. Same thing basically with the overdrive. Your RPM is lower with the overdrive but your torque needed to keep it there has gone up. Make sure your radiator is clean and that your thermostat is working well. You might also go with a lower temp thermostat.
Another way to look at it is towing a trailer. Your RPM is the same at 55mph but tow a trailer and at that same speed and RPM your engine is working much harder and getting hotter.

 

[Drock]

If it wasn't for dumb luck I'd have no luck at all. Well I got it installed today, and as it turns out our trucks already have the deep version of the trans pan that includes the filter extension. That being said there are 2 versions of this new (Derale) pan. A short and a deep. If I had gotten the shorter one it wouldn't have fit, hence my dumb luck. Also this new pan only ends up being 1-3/8" deeper then the stocker. It ended up being 2-1/2" above the trans crossmember so clearance is definitely not an issue. here's a pic.....