Transmission Heater bolts loose

[bigben542]

So I need some help and advice. I have a 2020 1500 Built to Serve edition Bighorn, 5.7 with just over 71,000 on the odometer. Last week I was towing my subcompact tractor to my dad’s house, and noticed when I got there that my tailgate looked like it was splashed with water though it was a dry day and I didn’t drive through any standing water. Checked it out closer and realized it was somewhat oily in consistency. I looked underneath and noticed a good bit of the undercarriage looked wet, but saw nothing dripping and didn’t smell anything out of the ordinary. I drove the short drive back to my house and got underneath to find that the transmission heater on the drivers side was very wet, then to notice that one of the bolts holding the 2 main pieces was sticking about a half inch or more out, and the other one was loose as well. So first thing I need to figure out by where it is coming from is if its tranny fluid that leaked out, which I am leaning towards, or coolant, which when I checked once cooled is actually very low. My next question is should I try to self diagnose/repair being pretty handy working on cars, or take it to the dealer knowing I’m past the Powertrain warranty mileage and doubt that they will help me out at all since apparently things were not torqued right that the bolts worked out so easily. Have not done any heavy towing and mostly highway mileage. Included pics of the area and where I noticed the leaking. Blue is the loose bolts, yellow is where I noticed the most leaking between the two components.

 

[crazy jerry]

handy with cars but didnt know if its trans oil or coolant. probly best just take it to a dealer

 

[bigben542]

Appreciate the reply, really classy of you. With the dirt under the truck mixed in with the fluid it’s impossible to tell the color of the fluid. Was hoping someone may have more knowledge about the path of flow of the fluids through the heater to maybe be able to tell me more. There’s no smell easily detectable which leads me to believe its trans fluid but with my coolant being low in the reservoir I’m questioning that, and hoping with the fact the bolts were that loose and there was a leak that there wasn’t a path for the coolant to enter the transmission and mix with the trans fluid. Perhaps someone with more to contribute will chime in.

 

[Atcer2018]

Appreciate the reply, really classy of you. With the dirt under the truck mixed in with the fluid it’s impossible to tell the color of the fluid. Was hoping someone may have more knowledge about the path of flow of the fluids through the heater to maybe be able to tell me more. There’s no smell easily detectable which leads me to believe its trans fluid but with my coolant being low in the reservoir I’m questioning that, and hoping with the fact the bolts were that loose and there was a leak that there wasn’t a path for the coolant to enter the transmission and mix with the trans fluid. Perhaps someone with more to contribute will chime in.

Unfortunately I don’t have any definitive answer for you. The oil heater/cooler units are known to go bad and yes they do leak. You may have two separate issues. A coolant leak and a transmission leak.

Many of us have gone with a simple bypass valve sold by forum member Caulk04. It eliminates the thermostat inside the cooler line. The bypass valve lowers the operating temps of the transmission by a good 20 degrees which is beneficial as heat kills transmissions. It’s not for everyone especially in the colder climates. I see you are in PA and with a nick like bigben maybe in the PIT area. Don’t know if Picks-burg has rough winters anymore as I left PA 30 years ago. The transmission will be slower to warm up with the bypass valve.

Personally I’d be more concerned with finding and correcting the low coolant issue. Have you tried pressure washing or using a couple cans of brake cleaner on the soiled area to get the grime off then driving it a few days and checking it again to determine what the substance is?

 

[bigben542]

Unfortunately I don’t have any definitive answer for you. The oil heater/cooler units are known to go bad and yes they do leak. You may have two separate issues. A coolant leak and a transmission leak.

Many of us have gone with a simple bypass valve sold by forum member Caulk04. It eliminates the thermostat inside the cooler line. The bypass valve lowers the operating temps of the transmission by a good 20 degrees which is beneficial as heat kills transmissions. It’s not for everyone especially in the colder climates. I see you are in PA and with a nick like bigben maybe in the PIT area. Don’t know if Picks-burg has rough winters anymore as I left PA 30 years ago. The transmission will be slower to warm up with the bypass valve.

Personally I’d be more concerned with finding and correcting the low coolant issue. Have you tried pressure washing or using a couple cans of brake cleaner on the soiled area to get the grime off then driving it a few days and checking it again to determine what the substance is?

Thanks for reply. I’m in eastern Pa and sometimes we do get frigid winters every few years. I did recently clean it off pretty well with some brake clean and only drove it a little bit yet with nothing new showing, will keep checking periodically. I’ve read about that bypass somewhat I would just have to look into more being like you said in a somewhat colder climate come winter time. The low coolant is where my attention is going to be as of now as well.

 

[JHoward]

Yeh, tighten the bolts and keep an eye on the coolent.

Does the tranny seem to be ok when driving?

I'm wondering if the tranny also lost a little fluid. To know that, for sure is to raise the back of your truck until the tranny pan is level and cool(88°~120°)with the engine running and unscrew the fill plug. 8mm hex key.

If nothing comes out, you'll need to add tranny fluid through the fill hole until fluid starts coming out of the fill hole.

Here's a pic of the tranny fill procedure.

 

[Atcer2018]

Thanks for reply. I’m in eastern Pa and sometimes we do get frigid winters every few years. I did recently clean it off pretty well with some brake clean and only drove it a little bit yet with nothing new showing, will keep checking periodically. I’ve read about that bypass somewhat I would just have to look into more being like you said in a somewhat colder climate come winter time. The low coolant is where my attention is going to be as of now as well.

Good deal, hope the loose bolts were the problem and it’s been corrected. Definitely look into the bypass as it does reduce the transmission temps. I don’t really notice any difference in cold weather performance but I am in SE Virginia. I grew up in the Allentown area.

 

[Wild one]

If those bolts were loose it'll be transmission fluid it leaked. The coolant in the heater stays in the heater,unless it develops a crack/fissure,and if it did,there's a good chance you wouldn't still be driving it,as the coolant would go directly inside the transmission,and it's only a matter of miles before the transmission self destructs.
Tighten the bolts up / check the fluid level,and call it good

 

[JHoward]

If those bolts were loose it'll be transmission fluid it leaked. The coolant in the heater stays in the heater,unless it develops a crack/fissure,and if it did,there's a good chance you wouldn't still be driving it,as the coolant would go directly inside the transmission,and it's only a matter of miles before the transmission self destructs.
Tighten the bolts up / check the fluid level,and call it good

Yep, that's what I'm thinking.

 

[bigben542]

Appreciate the replies, so far since I’ve tightened the bolts the area has stayed dry. I added some coolant to bring it back to where it should be, nothing lost and no leaks after some short trips the past few days. Temps seem to be holding where they should once warm for both coolant and transmission and no issues shifting or stumbling while driving. I am gonna check the trans fluid once I pick up a quart of the ZF fluid so that I have some ready should I need to add any. I’ll update of course once I perform that check.

 

[Wild one]

Appreciate the replies, so far since I’ve tightened the bolts the area has stayed dry. I added some coolant to bring it back to where it should be, nothing lost and no leaks after some short trips the past few days. Temps seem to be holding where they should once warm for both coolant and transmission and no issues shifting or stumbling while driving. I am gonna check the trans fluid once I pick up a quart of the ZF fluid so that I have some ready should I need to add any. I’ll update of course once I perform that check.

At 71,000 you're due for a transmission service.ZF says service the 8 speed between 50,000 and 80,000 miles.Might be time to bite the bullet and change the fluid/pan and filter.