EOC with AWD safe? Subaru Sti - Fuel Economy, Hypermiling, EcoModding News and Forum

jedi_sol · 08-13-2013, 03:19 PM

Hello all,
I tried doing a search for "eoc" and "awd" combinations and couldnt find anything relevant or concrete.

Is it safe to EOC with AWD? Will EOCing have any negative impact on AWD systems/drivetrains?

Car is a 2013 Subaru Sti

Thanks!

kaiba · 08-13-2013, 05:13 PM

Coasting with the AWD system shouldn't hurt the drivetrain at all in neutral or gear. I would be more worry about shock load to drivetrain when bump starting the engine.

cbaber · 08-13-2013, 05:35 PM

Your owners manual should tell you whether or not the car can be flat towed 4 wheels down. If it can, you are fine to EOC. Some drivetrains (mostly automatic) have lubrication systems that are required to be functioning or serious damage could occur when in neutral with the engine off.

Bump starting is fine if done properly. You aren't stressing the clutch/engine any more bump starting than you do shifting gears or starting from a dead stop.

ConnClark · 08-13-2013, 06:06 PM

Those two answers cover damage to your drive train.

But as far as safe goes, it depends on if you think EOC is safe to begin with.

Awd180 · 08-13-2013, 06:08 PM

Don't. But a subaru can be pop started and yes it has to be towed on a flat bed. I have bump started threw the ignition in neutral. Some other heads up, the tmic stays cooler while moving engine on, which you want, if you believe in the wai take your Hot side heat sheild off (you'll get misfires from the fuel auto igniting). My intake manifold is cool to touch after a nice drive. Also, the amount of heat from the hot side w/o sheild will cause electrical components to fail from prolong heat. There's more, but a lot comes from doing research and $$$$$.

UltArc · 08-13-2013, 06:32 PM

Quote:

Originally Posted by Awd180

Don't. But a subaru can be pop started and yes it has to be towed on a flat bed. I have bump started threw the ignition in neutral. Some other heads up, the tmic stays cooler while moving engine on, which you want, if you believe in the wai take your Hot side heat sheild off (you'll get misfires from the fuel auto igniting). My intake manifold is cool to touch after a nice drive. Also, the amount of heat from the hot side w/o sheild will cause electrical components to fail from prolong heat. There's more, but a lot comes from doing research and $$$$$.

The question to ask isn't if it should be towed flat bed or two wheels on the ground- that doesn't matter for this. What matters is if the car can be towed four wheels on the ground.

Unless Subaru is doing something new or strange, then I don't think it should be an issue. Either spool the engine up, and then engage transmission, or like I do sometimes (not the best method) put it back in gear rev matching. If I am in 6th, and above 26 mph, I just engage 6th. I don't know if it hurts any, but since I owned it, the synchros grind, and nothing NEW had occurred since I started doing that.

UltArc · 08-13-2013, 06:34 PM

I trust this source.

Awd180 · 08-13-2013, 06:44 PM

Quote:

Originally Posted by UltArc

The question to ask isn't if it should be towed flat bed or two wheels on the ground- that doesn't matter for this. What matters is if the car can be towed four wheels on the ground.

Unless Subaru is doing something new or strange, then I don't think it should be an issue. Either spool the engine up, and then engage transmission, or like I do sometimes (not the best method) put it back in gear rev matching. If I am in 6th, and above 26 mph, I just engage 6th. I don't know if it hurts any, but since I owned it, the synchros grind, and nothing NEW had occurred since I started doing that.

No it can't be towed on all fours, center diffs aren't cheap, you may push it 100yds or so but not towed at speed. I could be wrong, but in my research no one suggests towing any other way. However since its possible to rev match to launch at 60 in 3rd, it could very well work, Subaru's are notorious for having glass like gear boxes.

UltArc · 08-13-2013, 07:18 PM

Quote:

Originally Posted by Awd180

No it can't be towed on all fours, center diffs aren't cheap, you may push it 100yds or so but not towed at speed. I could be wrong, but in my research no one suggests towing any other way. However since its possible to rev match to launch at 60 in 3rd, it could very well work, Subaru's are notorious for having glass like gear boxes.

All four wheels spin the same. With a standard, out of gear, it's no issue. You're welcome to refer to what Subaru suggest, in the link I posted before this post.

Awd180 · 08-13-2013, 08:27 PM

Quote:

Originally Posted by UltArc

All four wheels spin the same. With a standard, out of gear, it's no issue. You're welcome to refer to what Subaru suggest, in the link I posted before this post.

i guess your right, it all depends. here's what subaru says

Manual Transmission:
All Wheel Drive vehicles can be towed with all four wheels on the ground or with all four wheels off the ground on a trailer but towing an AWD vehicle must never be attempted with only two wheels on the ground or two wheels on a dolly.

STI, to tow: DCCD must be in manual mode, with the DCCD control dial set to the furthest rearward position (rolled toward rear seat).

Not every sti or wrx has the ability to adjust the center dif

But as I also said a lot of owners have transmission woos.