Hey guys I have a freshly rebuilt transmission getting warm on me and what should I check? Have it at the tranny shop right now and they said everything checked out. They put a new bypass valve in it at no charge just to be sure that wasn't it. They said the trans cooler seems to be flowing like it should and it could possibly be a weak fan clutch causing the problem? Any thoughts here folks? Water temp doesn't go up above where it normally runs and I haven't let the trans get over 220. It only gets warm when it's in drive and I am stopped at a light. When I get rolling down the road it will cool off or stay where it's at. When in park it will not climb.

 

You'd have to be at that light a long time before the fan clutch comes on (normally).

Also, unless you have a separate coolant gauge installed, your stock WT indicator is nothing more than an "on/off" switch. Does not give you a temp indication other than normal or too hot.

 

Can you hold the fan blade still while the engine is running? I wear a thick leather glove and rest my hand on the fan shroud while holding the fan still with my fingers. Don't grasp the blade, just rest a couple of fingers on the back side of the blade against the direction of rotation and then have someone start the engine. If the fan forces your fingers off the blade then it's pulling air....if you are able to keep the blade still even while the engine is running then your fan clutch is faulty.

I've seen people use a broom handle or wooden dowel but that may crack your fan so I don't really like that method.

 

Sounds scary! Haha!

 

Yeah, it's a bit nerve racking the first time you try something like that. It's usually best to watch someone who has experience with the procedure so you can get the idea of how to do it safely. I'll try and record a video and post it online sometime.

If you are uncomfortable with using your hand then you can try and use something like a paint roller cover or anything stiff enough to get a positive purchase on the fan blade but soft enough so it doesn't damage anything.

 

Do you have a EOT gauge?

 

Wait... I need to wrap my (bald) head around this:

"My transmission is running hot."

"Grab the fan with the engine running."

"Really?"

"Oh... I should probably mention this too: Be careful."

Pull that chip out, chips frequently alter the transmission pressures. I don't know what yours does, but getting back to Stock never hurts.

 

No don't do that. Don't grab anything with the engine running. That would be crazy.

 

A cold fan clutch will be locked up enough to take your hand off. Don't even think about holding a fan with an engine running.

 

Tugly: I will do that

JMatthews: I do not have an EOT Guage, but I do have AE if that helps. My oil cooler orings need to be replaced. Will that possibly have something to do with it?

It's still at the transmission shop and I will pass this info over to them. Any other things to check?

While I'm on the subject, what is the difference between "trans cooler" and "intercooler"? I want to upgrade to the 6.0, but what to get?

 

Could it be the gauge or the sending unit? The temps in my experience don't climb or dissipate that quickly, climb maybe but dropping no. Especially since the TC isn't locked while driving around town at low speeds. What are you using to monitor tranny temps?

 

Trans cooler is hooked up to the Trans fluid lines and is kinda in front of the lower part of the radiator. Just follow the tranny fluid lines from the transmission. The intercooler cools the air charge after the turbo. Many folks upgrade the 7.3L Trans cooler to the bigger 6.0L trans cooler. In addition some exchange the stock intercooler with the 6.0L intercooler as well. This could be the source of the confusion.

 

I have Autometer gauges and the guys at the shop hooked up their Snap-On scanner, which is also reading that the tranny is warm. My gauge temp is off by 20 degrees cooler from their scanner. It will catch up with their scanner when the temp stabilizes while in park. So, I guess what I'm saying is my gauge is a little slow. Lol...

So, it can be just a sensor possibly?

 

What is the temp on the shops scanner and your gauge when u say it is warm?

 

Mine says 210 and theirs says 220..