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Thread: Can the manual 5 speed be Flat Towed?

  1. #11
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    100% DO NOT flat tow any vehicle unless it has provisions specifically for flat towing. The reason for this is that the bearings inside the transmission will be starved of lubrication. When the engine is running and the clutch is driving the input shaft, all gears are spinning (even in neutral). When the gears are spinning, they pick up fluid and sling it into channels that feed the bearings with lube.

    If a vehicle is moving in neutral with the engine off, the intermediate shaft is spinning inside the gears and no lubricant is getting into the bearings, however the gears themselves are not moving and are not carrying fluid for lubrication.

    Vehicles with transfer cases can be flat towed because the transfer case itself can be put into neutral and therefore the wheels do not drive the output side of the transmission. Certain vehicles like Saturns had very specific provisions to lubricate the output side of the transmission.


    '17 Mitsubishi Mirage 1.2L ES Plus 5MT
    '94 Ford Ranger 5.0 Turbo 3 Speed

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    i cant see any problem towing a manual, unlike cvt it does not require an oil pump to circulate its lubrication, manual gears just sits on a pool of gear oil and self lubricates itself.

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    Quote Originally Posted by allrock View Post
    i cant see any problem towing a manual, unlike cvt it does not require an oil pump to circulate its lubrication, manual gears just sits on a pool of gear oil and self lubricates itself.
    You still will not get lubrication unless the input shaft is spinning.

    Source: I may have rebuilt a few transmissions in my day.

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    Last edited by Pimp_Daddy_Patty; 06-11-2022 at 02:16 AM.
    '17 Mitsubishi Mirage 1.2L ES Plus 5MT
    '94 Ford Ranger 5.0 Turbo 3 Speed

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    Senior Member daleWV's Avatar
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    Quote Originally Posted by Pimp_Daddy_Patty View Post
    100% DO NOT flat tow any vehicle unless it has provisions specifically for flat towing. The reason for this is that the bearings inside the transmission will be starved of lubrication. When the engine is running and the clutch is driving the input shaft, all gears are spinning (even in neutral). When the gears are spinning, they pick up fluid and sling it into channels that feed the bearings with lube.

    If a vehicle is moving in neutral with the engine off, the intermediate shaft is spinning inside the gears and no lubricant is getting into the bearings, however the gears themselves are not moving and are not carrying fluid for lubrication.

    Vehicles with transfer cases can be flat towed because the transfer case itself can be put into neutral and therefore the wheels do not drive the output side of the transmission. Certain vehicles like Saturns had very specific provisions to lubricate the output side of the transmission.
    I respectfully disagree in the case of the F5MBD transmission used in the manual Mirage. If you look at the design of the power flow, with the engine off and the transmission in neutral and the car being towed, the transmission output shaft is spinning and 3rd, 4th, and 5th driven gears which are splined directly to the output shaft are also spinning. These gears will pick up lubrication and spread it to the 3rd, 4th, and 5th drive gears on the transmission input shaft and their needle bearings will be lubed. Nothing else will be spinning on the input shaft so no other lubrication is needed for it. The spinning output shaft end bearings will be lubricated in their normal manner as well as the 1st and 2nd driven gear needle bearings (remember any time the car is moving the entire output shaft is turning). Additionally oil from the differential section of the transaxle is bathing the transmission output shaft indirectly through the final drive gears also. IMHO I can really so no reason attributable to the transmission why the manual Mirage couldn't be flat towed.

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    Quote Originally Posted by daleWV View Post
    I respectfully disagree in the case of the F5MBD transmission used in the manual Mirage. If you look at the design of the power flow, with the engine off and the transmission in neutral and the car being towed, the transmission output shaft is spinning and 3rd, 4th, and 5th driven gears which are splined directly to the output shaft are also spinning. These gears will pick up lubrication and spread it to the 3rd, 4th, and 5th drive gears on the transmission input shaft and their needle bearings will be lubed. Nothing else will be spinning on the input shaft so no other lubrication is needed for it. The spinning output shaft end bearings will be lubricated in their normal manner as well as the 1st and 2nd driven gear needle bearings (remember any time the car is moving the entire output shaft is turning). Additionally oil from the differential section of the transaxle is bathing the transmission output shaft indirectly through the final drive gears also. IMHO I can really so no reason attributable to the transmission why the manual Mirage couldn't be flat towed.
    i agree with this, the level of oil is specifically leveled and designed to reach all moving components and bearings, and anything that spins inside even when towed or not, thats the reason why it doesn't need an oil pump.

  8. #16
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    Quote Originally Posted by daleWV View Post
    I respectfully disagree in the case of the F5MBD transmission used in the manual Mirage. If you look at the design of the power flow, with the engine off and the transmission in neutral and the car being towed, the transmission output shaft is spinning and 3rd, 4th, and 5th driven gears which are splined directly to the output shaft are also spinning. These gears will pick up lubrication and spread it to the 3rd, 4th, and 5th drive gears on the transmission input shaft and their needle bearings will be lubed. Nothing else will be spinning on the input shaft so no other lubrication is needed for it. The spinning output shaft end bearings will be lubricated in their normal manner as well as the 1st and 2nd driven gear needle bearings (remember any time the car is moving the entire output shaft is turning). Additionally oil from the differential section of the transaxle is bathing the transmission output shaft indirectly through the final drive gears also. IMHO I can really so no reason attributable to the transmission why the manual Mirage couldn't be flat towed.
    I'm definitely gonna have to revisit the diagrams then. I was certain all gears were on the same shaft for this transmission.


    '17 Mitsubishi Mirage 1.2L ES Plus 5MT
    '94 Ford Ranger 5.0 Turbo 3 Speed

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