Re: Manual Tran. Towing

It's a slow day on the board so I'll toss this in— I can't absolutely say you will damage the tranny if you don't disconnect the driveshaft. But I can absolutely say you won't damage it if you do disconnect the drive shaft.

Towing with the D-shaft connected means spinning the OD output flange, the OD innards, and the tranny mainshaft (aka output shaft). This always happens when coasting. If it didn't, we'd get no engine braking.

But with the tranny in Neutral the Input shaft does not spin, since the engine is not running. This means that the Idler Gear (aka Cluster Gear/Layshaft) won't be spinning either.

It's the spinning Idler Gear that normally provides the splash lubrication inside the tranny. Therefore, there will be NO LUBRICATION for the spinning mainshaft, its rear bearing, and all the needle bearings or bushings for the 1st, 2nd, and 3rd speed drive gears, synchro hubs, etc.—all riding that spinning mainshaft—with no oil splashing.

Many claim to have towed RWD cars without disconnecting the driveshaft and suffered no damage. I'd say no apparent or immediate damage. But what about possible shortened bearing/bushing life? It's not a gamble I'd want to take, when I can have the driveshaft uncoupled and tied to one side in 1/2 hour or so.

MotorHome magazine's web site and Pensketruckrental.com, among others, also recommend it.

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Bruce Young
'93 940-NA (current) — 240s (one V8) — 140s — 122s — since '63.