Automatic or Manual Transmission for Expedition Use?

[Deleted member 9101]

The clutch should never be used for shifting gears. It should be used to assist in shifting gears while speed matching the RPMs. Ever wonder why the syncros go out?

The clutch in a big truck is only used for starting off and stopping, never for shifting.

Ya can't float gears on a drag strip, jeep trail, while burried in a mud hole, or while fully loaded going up/down a hill.

Also "big trucks" are on a different level than a regular vehicle.

 

[Desert Dan]

Not many manual transmission choices in new vehicles/trucks in the US.

 

[lugueto]

We are not a modern vehicle though- the 81 series Land Cruiser is an early 1990s design.

The 80 series LCs are old tech, no doubt, but both their gearboxes have proven to be bomb proof stock. So its basically a toss up.

A prime example? The clutch should never be used for shifting gears. It should be used to assist in shifting gears while speed matching the RPMs. Ever wonder why the syncros go out?

The clutch in a big truck is only used for starting off and stopping, never for shifting.

Comparing a non-synchronized truck transmission to a regular car or SUV transmission is not entirely fair. While floating gears in a regular synchronized transmission is very possible in some conditions, recommending it to be done regularly would be downright irresponsible.

 

[TwinDuro]

An interesting discussion for sure! It sounds like both the manual and auto choices for the HDJ81 are reliable enough (when maintained), sounds like a toss up more based on preference and availability. I'm not a Landcruiser guy per se, but I would assume we're talking about the H150/H151 (For the manual) and the A442F for the auto? Both seem to be great transmissions.

I'm a manual transmission enthusiast myself and the vehicle I'm building up has one of the more robust overdrive manual transmissions that has ever been offered in a vehicle in north America. With that said, even though I love this particular transmission and some of the advantages it has in gearing for certain situations, if I were to build a specific rig for overland travel, I'd pick an auto every time. Ease of use, especially in stop and go traffic or over rough terrain would be the big reason. Modulating everything while navigating complicated areas or obstacles gets a little old with a manual after awhile: heel-toe sidestepping of the brake and throttle and a long-throw, high-effort clutch pedal makes what would be relatively simple task in a automatic rig a lot more work with a stick. Driver fatigue can and often does go up. Mechanical fatigue in the drivetrain also appears to be greater in a manual transmission rig. Shock loads _seem_ to be a little better managed with a automatic (torque converter) and a thoughtful pilot. Just my humble opinion.

I've had a clutch failure in a manual transmission and torque converter failure/pump failure in an automatic rig. Both were still able to limp to a safe spot to get checked out, although it was painful in both vehicles. Given an opportunity and the right situation, everything can and will fail. The key is have a good idea of what you'll do to handle it if and when it does.

I would would put an emphasis on making sure whatever you choose starts out healthy, stays healthy and has proper upgrades to maintain that if required and then just go for it... If both transmissions were 100% reliable, what would you choose @SoyBoy?

 

[roving1]

One thing people overlook as a benefit with manuals is the far superior engine braking and control you can get from a manual. It's so much nicer to drive in really mountainous terrain and off road. It's possible to barely need the brakes while descending steep grades and just need to tap the brakes at the sharpest switchbacks. Autos are really hard on the brakes in this scenario. Newer electronic 10 speed stuff can mitigate this somewhat but in older stuff it's night and day difference.

 

[SoyBoy]

An interesting discussion for sure! It sounds like both the manual and auto choices for the HDJ81 are reliable enough (when maintained), sounds like a toss up more based on preference and availability. I'm not a Landcruiser guy per se, but I would assume we're talking about the H150/H151 (For the manual) and the A442F for the auto? Both seem to be great transmissions.

I'm a manual transmission enthusiast myself and the vehicle I'm building up has one of the more robust overdrive manual transmissions that has ever been offered in a vehicle in north America. With that said, even though I love this particular transmission and some of the advantages it has in gearing for certain situations, if I were to build a specific rig for overland travel, I'd pick an auto every time. Ease of use, especially in stop and go traffic or over rough terrain would be the big reason. Modulating everything while navigating complicated areas or obstacles gets a little old with a manual after awhile: heel-toe sidestepping of the brake and throttle and a long-throw, high-effort clutch pedal makes what would be relatively simple task in a automatic rig a lot more work with a stick. Driver fatigue can and often does go up. Mechanical fatigue in the drivetrain also appears to be greater in a manual transmission rig. Shock loads _seem_ to be a little better managed with a automatic (torque converter) and a thoughtful pilot. Just my humble opinion.

I've had a clutch failure in a manual transmission and torque converter failure/pump failure in an automatic rig. Both were still able to limp to a safe spot to get checked out, although it was painful in both vehicles. Given an opportunity and the right situation, everything can and will fail. The key is have a good idea of what you'll do to handle it if and when it does.

I would would put an emphasis on making sure whatever you choose starts out healthy, stays healthy and has proper upgrades to maintain that if required and then just go for it... If both transmissions were 100% reliable, what would you choose @SoyBoy?

I have never driven a RHD manual just an automatic.
Most of my LHD vehicles are manual.
If I could find a LHD diesel - it would like it to be a manual.
If I were to buy a RHD I'd probably prefer it be an automatic.

Having said that - I am currently dealing on a nice RHD manual that is 800 miles away - when we are closer to closing the deal I will drive out there to give it a try - chances are I will get used to it fairly quickly.

So - I guess I am open to what the market has to offer. A diesel engine is important for me. My gold standard would be a 105 LHD diesel manual.

 

[SoyBoy]

One thing people overlook as a benefit with manuals is the far superior engine braking and control you can get from a manual. It's so much nicer to drive in really mountainous terrain and off road. It's possible to barely need the brakes while descending steep grades and just need to tap the brakes at the sharpest switchbacks. Autos are really hard on the brakes in this scenario. Newer electronic 10 speed stuff can mitigate this somewhat but in older stuff it's night and day difference.

All good points you have brung up. THX

 

[Amazigh]

Manual for me, too much cost and headache when a auto box fails. Can't say I ever get tired of changing gear.

2015 I ran a trip for 8 landcruisers to North Africa, 2 cars had gearbox issues, both auto boxes. Something to consider is that Toyota only fit a manual in the 70 series and most Africa spec 80's and 100 series are also manual only cars, I expect that's either cost or more likely that Toyota believe the manual is a tougher option

 

[lugueto]

One thing people overlook as a benefit with manuals is the far superior engine braking and control you can get from a manual. It's so much nicer to drive in really mountainous terrain and off road. It's possible to barely need the brakes while descending steep grades and just need to tap the brakes at the sharpest switchbacks. Autos are really hard on the brakes in this scenario. Newer electronic 10 speed stuff can mitigate this somewhat but in older stuff it's night and day difference.

Engine braking on an automatic is just as feasible as a manual. Sure, when you compare engine braking in a 5 speed manual vs a 4 speed auto, the auto will feel like its worse. You don't have to have 10 speeds to mae it feel more like a manual, A750F 5 speeds have no problem selecting gearing as well, you can shift any gear you like at any time.

If you have a longer ratio 4 speed transmission (Think A442F or A343F) where you can select, 2nd or 1st (or even 3rd using the OD Off button). You can go down a hill in 2nd or 1st just fine. As said, ratios in manuals are usually shorter but instead of going down a hill in 2nd on a manual, you'll be going down in 1st in the auto. If that ain't enough, you should be in low range anyway.

Something to consider is that Toyota only fit a manual in the 70 series and most Africa spec 80's and 100 series are also manual only cars, I expect that's either cost or more likely that Toyota believe the manual is a tougher option

3rd world specs are usually more biased toward cost and ease of repairs.

The 70 series would be particular example. They're only offered with manuals. The only auto 70s out there are Prados and LC2s (light duty version that migrated to the 90 series). 80s and 100s are found in both, and outside the US I'd say they're pretty evenly distributed between the two gearboxes.

 

[roving1]

Engine braking on an automatic is just as feasible as a manual. Sure, when you compare engine braking in a 5 speed manual vs a 4 speed auto, the auto will feel like its worse. You don't have to have 10 speeds to mae it feel more like a manual, A750F 5 speeds have no problem selecting gearing as well, you can shift any gear you like at any time.

If you have a longer ratio 4 speed transmission (Think A442F or A343F) where you can select, 2nd or 1st (or even 3rd using the OD Off button). You can go down a hill in 2nd or 1st just fine. As said, ratios in manuals are usually shorter but instead of going down a hill in 2nd on a manual, you'll be going down in 1st in the auto. If that ain't enough, you should be in low range anyway.



3rd world specs are usually more biased toward cost and ease of repairs.

The 70 series would be particular example. They're only offered with manuals. The only auto 70s out there are Prados and LC2s (light duty version that migrated to the 90 series). 80s and 100s are found in both, and outside the US I'd say they're pretty evenly distributed between the two gearboxes.

I disagree. Unless you can manually lock the torque converter up while coasting it's not an apples to apples comparison, also not apples to apples between diesels and gas engines which can skew perception if you are used to a diesel/auto combo and assume the gas/auto combo is the same.

Throw in the fact, with Toyotas especially, the auto gearing is often terrible and the manual is often much better and it's even more pronounced.

It's super obvious when traveling in mixed groups where the auto vehicles are always trying to run over the manuals while having to use the brakes more or travel drastically slower 1-2 gears lower to compensate.

 

[TwinDuro]

I have never driven a RHD manual just an automatic.
Most of my LHD vehicles are manual.
If I could find a LHD diesel - it would like it to be a manual.
If I were to buy a RHD I'd probably prefer it be an automatic.

Having said that - I am currently dealing on a nice RHD manual that is 800 miles away - when we are closer to closing the deal I will drive out there to give it a try - chances are I will get used to it fairly quickly.

So - I guess I am open to what the market has to offer. A diesel engine is important for me. My gold standard would be a 105 LHD diesel manual.

That all makes perfect sense @SoyBoy. Indeed, a 105 LHD diesel would be incredible although the seem as rare as hens teeth in this part of the world. Just out of curiosity, what is parts availability like for an imported diesel 80 series LC's like in your part of Canada?

 

[SoyBoy]

That all makes perfect sense @SoyBoy. Indeed, a 105 LHD diesel would be incredible although the seem as rare as hens teeth in this part of the world. Just out of curiosity, what is parts availability like for an imported diesel 80 series LC's like in your part of Canada?

Because I'm still looking I have no first-hand experience with getting parts. Having said that I spoke with the local LC dude who owns an independent shop for Toyotas said he has had a few diesels built and never made any comment that parts were tough to find. Most parts are the same as all NA 80s except the obvious. He said ordering parts from Japan or Australia is pretty much a slam dunk these days.
Hope that answers your question.
No - I was never expecting to get a 105 here - but I considered buying a nice one in South Africa (to use there) before covid happened (I was considering bringing a Troopy in for the longest time - now the 80 diesel is what I'm hunting for - smaller and more nibble)

 

[billiebob]

Ya can't float gears on a drag strip, jeep trail, while burried in a mud hole, or while fully loaded going up/down a hill.

Also "big trucks" are on a different level than a regular vehicle.

thank you, all these guys claiming they float gears while wheeling, please post the youtube video doing it

this is my favourite no clutch shifting video

 

[SoyBoy]

Must live in a bubble cuz I never heard no-clutch referred to as floating gears. - Guess I've been floating gears on my motorcycles for years - not so much in my cars!

 

[Red90]

Must live in a bubble cuz I never heard no-clutch referred to as floating gears. - Guess I've been floating gears on my motorcycles for years - not so much in my cars!

It is a bit of apples and oranges. A bike has non synchronized gears. The same is true with large trucks. These are easier to shift without a clutch than synchros.