Community Forums

FabPhae · 12-23-2022, 12:10 PM

Thanks Jeff! Tiffin said it was ENGINE coolant. So is there a different coolant for the Allison Transmission or do they work together? I have a good diesel guy that is going to look at it on Tuesday. Will update after that.

BradS · 12-24-2022, 08:09 AM

The hot transmission fluid circulates through the external (not part of the radiator) transmission cooler. The not too hot radiator coolant also circulates through the cooler where it exchanges heat with transmission fluid.

There is a sticker on the radiator overflow tank indicating the type of coolant required. Mine specifies "Final Charge". It can be purchased at Walmart in already diluted 50/50 gals.

jlturner · 12-24-2022, 08:24 AM

Quote:

Originally Posted by BradS

The hot transmission fluid circulates through the external (not part of the radiator) transmission cooler. The not too hot radiator coolant also circulates through the cooler where it exchanges heat with transmission fluid.

There is a sticker on the radiator overflow tank indicating the type of coolant required. Mine specifies "Final Charge". It can be purchased at Walmart in already diluted 50/50 gals.

Correct! Allison trans fluid “Transynd” is clear or light yellow color and the Final Charge coolant is pinkish red. Mine was leaking Final Charge on one of the welds. I would wipe off one day and check the next day. More drips!! :-(

TravelnPop&Nan · 12-26-2022, 09:32 AM

The cover over the motor is in the rear bath on mine. After the trip home from buying our RV, there was road dirt all over the floor in the rear bath. So I needed to seal up motor cover access! It was a bit of a challenge to get the cover off. Due to a problem when they built the floor for the closet. The right corner of the fake vent opening was built on top of the floor cover. I had to cut out part of the corner to the right 1/2”or so, back 1/2”or so, and up 2”or so to get the right corner of cover to be able to lift. Then I covered it up with foil tape to match. The cover has to be lifted up closest to the closet and slid to the back of the coach. You will need two glass suction cups, if it is like mine with tile floors. Trying to use a screwdriver or metal off any kind in the gap between the the tiles can risk cracking the a tile. The cover it is a bit heavy so the suction cups made it fairly easy to get off and on. I am glad I found the issue. because I was able to do a clean job fixing it. No one will know it was a problem to begin with. After the cover is off there is a lot of room to look at the top of the motor and all around it, you may be able to see where it is leaking?

Old Scout · 12-26-2022, 09:45 AM

My wager is coolant from back of engine heater port [hose clamp]. Be surprised if tranny or engine were leaking fluid or oil on a new rig. My ISL had a fuel leak from the lift pump--appeared to be coming from the bell housing drain hole--but was just collecting there from external leak. Suspect if you run your finger inside the drain hole, it will be dry.

hmitchmd · 12-27-2022, 04:02 PM

I had a coolant leak that showed up when it was cold. The leak was at the hose clamp where it connects to pump. It wasn’t that easy to see that clamp or to tighten it well. Mobile diesel tech told me to stay put and he came to me. I was lucky because it was about ready to come off.

FabPhae · 12-28-2022, 02:47 PM

Update on leak;

I took the coach to my diesel mechanic, biting my nails all of the 6 miles over.... Arrived with no issue.

Mechanic found the coolant inlet hose, right above where the leak was coming out, was loose. 3 full turns to tighten; he checked other fittings as well. It was a gallon low on antifreeze which was added. He was very confident this had fixed the problem.

Thanks for all of the feedback and suggestions! Definitely another learning experience!

FabPhae · 01-09-2023, 07:01 AM

I had the chassis guys in Red Bay check the repair my mechanic made as well as check the other engine/transmission hoses for tightness. My mechanic had fixed the problem, and the Tiffin guys found a couple of more mildly loose hoses. Said they needed only half a turn or so on the clamps.

I feel good that this is completely fixed!