Noob Question - Pulling in Reverse?

[PJorgen]

Hope this question isn't too "noobish" or hasn't been beaten to death in another thread. I think I recall reading somewhere that if you need to extract a stuck vehicle, the extracting vehicle should not pull in reverse. Something to do with the way the teeth engage between the ring and pinion gears or that diffs don't lock up as well in reverse, or that the drive train is generally not as strong in reverse. Or something totally different?

Is any of this true? If so, how bad is it if one has to pull in reverse due to inability to turn around on the trail?

Thanks for the advice.

 

[Buliwyf]

Axles will be fine. Depends on the vehicle, but some manual trans have weak reverse gears.

Dig ramps with a shovel, then gently pull in reverse with any decent modern vehicle, and you should be ok. People that grab chains and ropes before shovels, not so much.

 

[nwoods]

PJorgen, i have been taught the same thing. That the reverse gear in the tranny Is not as robust as the forward gears. This came from Bill Burke in a training session i attended a few years ago, so i assume its legitimate.

 

[billiebob]

Hope this question isn't too "noobish" or hasn't been beaten to death in another thread. I think I recall reading somewhere that if you need to extract a stuck vehicle, the extracting vehicle should not pull in reverse. Something to do with the way the teeth engage between the ring and pinion gears or that diffs don't lock up as well in reverse, or that the drive train is generally not as strong in reverse. Or something totally different?

Is any of this true? If so, how bad is it if one has to pull in reverse due to inability to turn around on the trail?

Thanks for the advice.

All true. Not sure it is critical with passenger vehicles but recovering an oil field truck from a muskeg bog yes, critical when the option is there. The ring gear has a twist, one direction pushes the gears together increasing the power, reverse pulls them apart. Not sure the locker feels the difference.... but depending on the design maybe. Ring and pinion, yes for sure, they are designed to pull, not push. This is true even for a Prius.

Modern transmissions, I doubt there is a difference. Old 4 speeds with granny low, yes, for sure. Remembering 1970s Ford 4 speeds, they were technically 3 speeds with a deep first gear. You would always start in second. First was bull low. 2, 3, 4 were short shifts, 1st tho was a longer throw because bull low used wider gears. Today that is not true......... hell today you cannot buy a truck with a clutch.

These are generic answers for the big three in North America. They build trucks for idiots. IF you drive a Euro, Aussie, Asian, African truck, I have no doubt some of those transmissions are old school for guys who know how to drive.

 

[Cav 3724]

Sometime take a look at a ring and pinion gear set. There is a distinct difference between one side of gears versus the other. One side, drive side, is more of a flat surface. The other side, coast side is more of a tapered surface. I've always been told that the drive side is designed to be the strongest, thus if possible pull forward. I've seen destroyed diff's from being used in reverse excessively. One look will explain it.

 

[outback97]

I have tried to find some pictures or a video describing why the gears are weaker in reverse; this is a pretty decent explanation:

Toyota 4Runner Technical Information

 

[KENPERK]

broke the front spider gears in my flat fender while pulling in reverse once..

 

[DaveInDenver]

I've never heard about reverse gear in a transmission being weaker but ring & pinions gears are stronger in one direction (drive) than the other (coast). So loading them backwards can strip the gear teeth off in theory. It's not just pulling a stuck vehicle but just any time you might stress them, like reversing uphill backwards is especially tough on front axles. Not only are you loading them in reverse but you also transfer the weight of the truck to the front axle.

 

[Buliwyf]

We're seeing excessive ring and pinion wear due to engine brakes. But mostly in pickups. Gear oil might be the difference.
Other than that, I doubt you'll hurt the axle gears without doing anything catastrophically stupid.

Manual trans have the weakest reverse gears. Usually modern auto trans uses two forward gears to get reverse. Not usually a big deal.
Wimpy lil idler shaft:

 

[Metcalf]

Some bad info brewing in here about ring and pinion directions......

If the front differential is low pinion, it will be stronger in reverse.
If the front differential is high pinion, it will be stronger going forwards.

Flip that around for the rear diff ( and pretty much every production rear differential is going to be low pinion )

Generally, if you are pulling on a stuck vehicle hard enough to break gears, you are doing it wrong.
Use more kinetic recovery straps/ropes to soften the impact
Use more shovel on the stuck vehicle

It isn't uncommon at all to give the leading vehicle a little tug backwards when they get stuck ( with the pulling vehicle driving backwards )
Having to flip the vehicle around every time to pull 'the correct way' just isn't practical and likely introduced more risk than it solves.

 

[Todd n Natalie]

You know what they say about pinions. Pinions are like butt holes. Everybody's got one and they all think theirs don't stink.

At least I'm pretty sure that's how that expression goes......