WORDS AND IMAGES MARK ALLEN

RE-GEAR YOUR TOW VEHICLE 

Fifth gear on pre-2017 V8 70 Series LandCruisers are notoriously short, returning a relatively high revving and loud long-distance highway drive experience – not nice day in and day out!

In 2017 Toyota saw fit to change the 70 Series box ratios of second and fifth cogs by 7 and 15 percent respectively. I could have shopped around for a later model (than my 2011 Troopy) box to slot in, but didn’t really want my second gear to be higher than what I had, which is low enough and useable enough for towing and general off-road work with little need to change.

To help with long-distance mile munching 

REVIEW Terrain Tamer modified ratio gear kit

In this episode of CruisemasterClass Andrew takes a look at electric drum brakes; how they work and how to
adjust them.
This is a must see for all caravan and camper trailer owners!

Follow the series on

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SCROLL TO CONTINUE WITH CONTENT

Enter Terrain Tamer’s modified ratio gear kit for the gearbox, which leaves second as standard but changes fifth gear by plus 20 percent – perfect! The complete gear set is a one-piece unit comprising first to fifth plus reverse cogs and is manufactured in Japan with hardened steel with a Rockwell rating of 62 – that means it’s damn hard and high quality.

I dished out for the Terrain Tamer kit, had a gearbox mob pull down the box and stuff it full of the new kit, which effectively changes the fifth cog from 0.881 to 0.736 to provide a theoretical change of around 400rpm.

While 400rpm may seem a minimal drop, the long-term highway cruising fuel savings will make a good difference to my hip pocket, albeit won’t pay for itself anytime soon. The noise difference makes up for that; given the 70 Series are commercial vehicles with little-to-no soundproofing as standard, the intrusive road and driveline noise is annoying over time. Obviously this lowering of revs can’t ever convert my Troopy to a 200 Series luxo-barge, but it has helped considerably.

GEARED DOWN – THE RESULTS
Standard gearing in my Troopy saw it clocking 2200rpm at 100km/h and 2500rpm at 110km/h; compared to the Terrain Tamer kit, returning just 1800 and 2100rpm at 100 and 110km/h respectively.

That confirms perfectly the theoretical reduction of 400rpm.

Terrain Tamer modified gear set
Standard gearing
zenith
inspire

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The downsides: any upping of gear ratios puts more stress on the driveline with potential over-gearing, creating more labour for the engine. This can cause higher fuel usage and less ability to use that higher gear set if the engine can’t deliver enough torque at the right revs. Given I have a DPChip that can be turned off, this allowed me to test my engine close to standard, other than the three-inch TaipanXP exhaust system and 33-inch rubber. Indeed, the engine struggled a little on long and steeper hills on the highway at 100 and 110km/h. There were occasions where I needed to downshift to fourth that I had always been able to tackle in fifth with standard gearing.

With the DPChip turned back on and set at position three as per usual (which was deemed safe and reliable via the installer), returning 131kW and 747.5Nm, there was little need to fiddle with the gearstick over the same roads. Towing a camper or caravan has seen more downshifting than normal and that’s where even higher returns of safe tuning will help. That leaves you with a taller fifth that can be used most of the time, but requires the occasional downshift to prevent labouring.

All up, while this mod may not pay for itself for a very long time, the pleasure and security of a quieter cabin via the lower-revving engine was well worth the exercise.

The Terrain Tamer modified ratio gear kit costs $1197 plus fitting. For more information see terraintamer.com

LEFT Terrain Tamer modified ratio gear kit for 70 Series Cruisers // BELOW Terrain Tamer change the ratio of fifth cog from 0.881 to 0.736 to provide a theoretical change of around 400rpm

REVIEW Terrain Tamer modified ratio gear kit

To help with long-distance mile munching 

RE-GEAR YOUR TOW VEHICLE 

Fifth gear on pre-2017 V8 70 Series LandCruisers are notoriously short, returning a relatively high revving and loud long-distance highway drive experience – not nice day in and day out!

In 2017 Toyota saw fit to change the 70 Series box ratios of second and fifth cogs by 7 and 15 percent respectively. I could have shopped around for a later model (than my 2011 Troopy) box to slot in, but didn’t really want my second gear to be higher than what I had, which is low enough and useable enough for towing and general off-road work with little need to change.

WORDS AND IMAGES MARK ALLEN

In this episode of CruisemasterClass Andrew takes a look at electric drum brakes; how they work and how to
adjust them.
This is a must see for all caravan and camper trailer owners!

Follow the series on

SCROLL TO CONTINUE WITH CONTENT

ADVERTISEMENT

Enter Terrain Tamer’s modified ratio gear kit for the gearbox, which leaves second as standard but changes fifth gear by plus 20 percent – perfect! The complete gear set is a one-piece unit comprising first to fifth plus reverse cogs and is manufactured in Japan with hardened steel with a Rockwell rating of 62 – that means it’s damn hard and high quality.

I dished out for the Terrain Tamer kit, had a gearbox mob pull down the box and stuff it full of the new kit, which effectively changes the fifth cog from 0.881 to 0.736 to provide a theoretical change of around 400rpm.

While 400rpm may seem a minimal drop, the long-term highway cruising fuel savings will make a good difference to my hip pocket, albeit won’t pay for itself anytime soon. The noise difference makes up for that; given the 70 Series are commercial vehicles with little-to-no soundproofing as standard, the intrusive road and driveline noise is annoying over time. Obviously this lowering of revs can’t ever convert my Troopy to a 200 Series luxo-barge, but it has helped considerably.

GEARED DOWN – THE RESULTS
Standard gearing in my Troopy saw it clocking 2200rpm at 100km/h and 2500rpm at 110km/h; compared to the Terrain Tamer kit, returning just 1800 and 2100rpm at 100 and 110km/h respectively.

That confirms perfectly the theoretical reduction of 400rpm.

Standard gearing
Terrain Tamer modified gear set

SCROLL TO CONTINUE WITH CONTENT

ADVERTISEMENT

The downsides: any upping of gear ratios puts more stress on the driveline with potential over-gearing, creating more labour for the engine. This can cause higher fuel usage and less ability to use that higher gear set if the engine can’t deliver enough torque at the right revs. Given I have a DPChip that can be turned off, this allowed me to test my engine close to standard, other than the three-inch TaipanXP exhaust system and 33-inch rubber. Indeed, the engine struggled a little on long and steeper hills on the highway at 100 and 110km/h. There were occasions where I needed to downshift to fourth that I had always been able to tackle in fifth with standard gearing.

With the DPChip turned back on and set at position three as per usual (which was deemed safe and reliable via the installer), returning 131kW and 747.5Nm, there was little need to fiddle with the gearstick over the same roads. Towing a camper or caravan has seen more downshifting than normal and that’s where even higher returns of safe tuning will help. That leaves you with a taller fifth that can be used most of the time, but requires the occasional downshift to prevent labouring.

All up, while this mod may not pay for itself for a very long time, the pleasure and security of a quieter cabin via the lower-revving engine was well worth the exercise.

The Terrain Tamer modified ratio gear kit costs $1197 plus fitting. For more information see terraintamer.com

LEFT Terrain Tamer modified ratio gear kit for 70 Series Cruisers // BELOW Terrain Tamer change the ratio of fifth cog from 0.881 to 0.736 to provide a theoretical change of around 400rpm

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