# Transmission fluid leaking out of radiator/coolant overflow tank **URL:** \ **Category:** Maintenance/Repairs\ **Created:** [December 11, 2019, 9:14pm UTC](https://community.cartalk.com/t/transmission-fluid-leaking-out-of-radiator-coolant-overflow-tank/154490 "2019-12-11T21:14:00Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![JDV](https://avatars.discourse-cdn.com/v4/letter/j/cab0a1/32.png) [@JDV](https://community.cartalk.com/u/JDV)\ **Post date:** [December 11, 2019, 9:14pm UTC](https://community.cartalk.com/t/transmission-fluid-leaking-out-of-radiator-coolant-overflow-tank/154490/1 "2019-12-11T21:14:00Z")
I own a V6 2008 Honda accord with an automatic transmission. After driving home (about 15 minutes) I noticed a weird smell and some smoke coming out of the hood of my car once I parked. When I popped the hood open I noticed a red-like fluid leaking out of the hose that connects to the coolant overflow tank. I immediately went back inside my car and checked the temperature but it was normal so it did not overheat. I also checked both my transmission fluid and my regular oil. My engine oil was normal but my transmission fluid was empty at that point. So I then assumed that all of the liquid that was leaking out was the transmission fluid and it was quite a lot of it which is safe to assume that it happened shortly before I arrived home so hopefully no major damage was done. I also checked the dipstick for any moisture to see if there was any water but it was all clean aside from a few spots of trans fluid. I did not drive the car any further and only when I was parking was when I noticed that it was a little slower on switching gears (reverse to D) but it was minimal. My question is, will simply changing the radiator fix this problem? Or do I need to do more extent work to it? Sorry if this is long but i just wanted to cover all the details. ---
**Author:** ![Tester](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/tester/32/15976_2.png) [@Tester](https://community.cartalk.com/u/Tester)\ **Post date:** [December 11, 2019, 9:16pm UTC](https://community.cartalk.com/t/transmission-fluid-leaking-out-of-radiator-coolant-overflow-tank/154490/2 "2019-12-11T21:16:00Z")
All you can do is replace the radiator, refill the transmission, and cross your fingers. Tester ---
**Author:** ![oldtimer-11](https://avatars.discourse-cdn.com/v4/letter/o/e79b87/32.png) [@oldtimer-11](https://community.cartalk.com/u/oldtimer-11)\ **Post date:** [December 11, 2019, 9:21pm UTC](https://community.cartalk.com/t/transmission-fluid-leaking-out-of-radiator-coolant-overflow-tank/154490/3 "2019-12-11T21:21:21Z")
I would replace the radiator, get the cooling system flushed and get a transmission fluid exchange with filter change. ---
**Author:** ![old\_mopar\_guy](https://avatars.discourse-cdn.com/v4/letter/o/6bbea6/32.png) [@old\_mopar\_guy](https://community.cartalk.com/u/old_mopar_guy)\ **Post date:** [December 11, 2019, 9:43pm UTC](https://community.cartalk.com/t/transmission-fluid-leaking-out-of-radiator-coolant-overflow-tank/154490/4 "2019-12-11T21:43:11Z")
- 1 to Tester, but be prepared to change the transmission earlier than you planned to. ---
**Author:** ![JDV](https://avatars.discourse-cdn.com/v4/letter/j/cab0a1/32.png) [@JDV](https://community.cartalk.com/u/JDV)\ **Post date:** [December 11, 2019, 9:47pm UTC](https://community.cartalk.com/t/transmission-fluid-leaking-out-of-radiator-coolant-overflow-tank/154490/5 "2019-12-11T21:47:32Z")
given that there was no sign of water in the tranny, how long do you think it would last? I know it’s hard to come up with an answer but maybe a time estimate? @old_mopar_guy ---
**Author:** ![old\_mopar\_guy](https://avatars.discourse-cdn.com/v4/letter/o/6bbea6/32.png) [@old\_mopar\_guy](https://community.cartalk.com/u/old_mopar_guy)\ **Post date:** [December 11, 2019, 9:50pm UTC](https://community.cartalk.com/t/transmission-fluid-leaking-out-of-radiator-coolant-overflow-tank/154490/6 "2019-12-11T21:50:44Z")
I don’t wish to be flip, but it will run until it doesn’t. No one can.predict when that will be.