General Altimax RT45 vs RT43

As grand touring all-season tires, the General Altimax RT45 and its predecessor, the RT43 both offer a balance of comfort, efficiency, and year-round performance. But is the newer tire better? Let’s find out!

As a tire engineer, my tests indicate that the General Altimax RT43 excels in ride and noise comfort, along with wet braking, while the RT45 stands out in fuel efficiency and handling in both dry and wet conditions. Plus the newer tire also takes the lead in winter conditions too, providing superb steering responsiveness.

Info on Sizes

The General Altimax RT45 comes in 14 to 20 inches rims with following specs.

• Speed ratings: T, H and V.
• Load ratings: SL and XL.
• Tread depth: 11/32″ on all.
• Weight range: 15 to 31 lbs.
• Warranty: 75k miles for H and T, or 65k miles for V-speed rated sizes
• UTQG rating: 600 and 700 A A.

The General Altimax RT43 comes in 13 to 20 inches rims with following specs.

• Speed ratings: T, H and V.
• Load ratings: SL and XL.
• Tread depth: 10, 11, and 12/32″.
• Weight range: 14 to 33.4 lbs.
• Warranty: 75k miles for H and T, or 65k miles for V-speed rated sizes
• UTQG rating: 600 and 700 A A.

Both tires have Replacement Tire Monitor (RTM) and Visual Alignment Indicators (VAI) telling you about wear and alignment, respectively.

Internal Construction: Both tires have single ply polyester casing and dual steel belts. Though RT45 comes with a single ply nylon cap, while RT43 offers two layers of spirally wrapped polyamide on top (of its steel belts).

Just so you know: For a well-informed tire choice, don’t skip my main all-season tire page.

Impact Comfort

Ride comfort is the first thing you notice with any tire. So its the first performance aspect I’m going to discuss here.

And interestingly in this aspect, the predecessor, General Altimax RT43, holds an advantage due to its relatively softer tread compound, which is more effective at smoothing out road imperfections.

Basically, this tire utilizes a dual-zone tread compound: one zone contains high-density silica, which keeps the rubber softer and enhances cushioning, while the other zone is stiffer, providing improved stability.

This combination results in more effective dampening of bumps, though it does lead to a trade-off with a somewhat less responsive steering feel, particularly a dull on-center sensation.

In contrast, the Altimax RT45, while aiming to enhance steering response, does not feature the same “Twin Cushion Silica Tread Compound” (as General likes to put it). So it falls short in overall impact comfort performance, comparatively.

Fuel Economy

Fuel efficiency in tires is influenced by several key factors:

• Tire Weight: The weight, influenced by both the internal and external structure, affects the overall efficiency.
• Rolling Resistance: This metric assesses how effectively a tire maintains contact with the road surface without creating excessive drag.
• Rubber Composition: The integration of specific polymers can enhance fuel economy while still providing adequate grip.

And consider all, it can be seen why the General Altimax RT45 does better here, thanks to its relatively stiffer rubber and lighter structure.

As previously mentioned in the section discussing ride comfort, the RT45 does not employ the Twin Cushion Silica Tread Compound found in the RT43. While this may compromise a bit on comfort, it pays off in terms of fuel efficiency.

And its a great news given that the tire despite giving off superior grip (which increases its rolling friction) still keeps showing better mpg readings (on my tests). Guess its a win win for RT45.

Dry Performance

Performance of a tire in dry conditions is best learned by analyzing longitudinal grip and cornering separately.

Longitudinal Grip

Directional traction, which is the ability of a tire to maintain straight-line control, is assessed by measuring braking distances. This traction is largely dependent on the tire’s contact area with the road and the efficiency of its tread design.

In this regard, the General Altimax RT45 demonstrates better performance, primarily due to its robust central ribs that are thicker and feature advanced, precisely angled biters.

To be more specific, the tire’s design includes a wider and more uniform central rib, which ensures consistent and strong contact with the road, leading to superior braking capabilities.

Additionally, RT45 incorporates thoughtfully designed features such as optimally angled notches, linear siping, chamfered edges, and “Y-shaped” in-block biters on adjacent ribs, enhancing its grip and traction further.

Moving towards its predecessor, the RT43 falls short, mainly because of its narrower central (most) rib.

Plus, the tire is also heavier in comparison as well. And that combined with its more open tread design results in greater pressure on each tread block. And, consequently, a larger weight is distributed over a smaller area of rubber, increasing the tire’s momentum inertia. So tire takes longer to stop (as seen on my 60 to 0 mph tests, on average).

For Your Info: Although the RT45 shows improvements, both tires could benefit from enhanced “on-center” stability. This refers to a tire’s ability to realign itself after completing a turn.

Lateral Grip and Handling

Handling is a better way of measure tire’s overall dry performance, as it involves all other metrics, including braking, lateral traction, and steering response. Why? Well it can be explained understanding the 3 phases of a corner.

• Entry Phase: This initial stage involves the vehicle preparing for the turn, often requiring braking and sometimes downshifting.
• Mid-Cornering: At the apex of the turn, precision in steering and maintaining grip are the most important here.
• Exit Phase: This final stage focuses on realigning the vehicle and smoothly resuming acceleration.

The General Altimax RT45 excels in all these stages, particularly standing out for its precise steering. Its strong braking capability contributes to a faster and more controlled entry into corners.

Additionally, the tire demonstrates excellent cornering grip (as indicated by lateral g-forces) and responsive steering, facilitating quicker and more efficient mid-cornering performance.

And once the corner is over its superior or, to say it better, “heavier” steering provides relatively better on-center feedback, (even though there’s room for improvement here still).

So, with RT45 excelling in all these phases, its able to provide a whole second faster handling as seen on lap time tests on average.

In contrast, the General Altimax RT43 lags behind, particularly in on-center and mid-cornering feedback.

This is again due to its heavier weight, causing its lugs to flex more taking time to recover and showing up as a delay between steering inputs and outputs from the wheels.

Wet Performance

How well tire performs under wet conditions can be summed by its overall traction, and resistance to hydro or aquaplaning. Let’s analyze both of these metrics separately.

Wet Grip and Handling

In wet conditions, both tires show competent performance, but to truly grasp their effectiveness, it’s important to understand the roles of sipes and grooves in tire design.

Grooves serve as the main pathways for water expulsion from beneath the tire, while sipes play a key role in absorbing any remaining moisture. These sipes flex to create a vacuum-like effect, drawing in water particles and enabling the rubber and tread elements to maintain consistent contact with the road surface.

Having said that, the General Altimax RT45 generally outperforms, particularly in providing superior steering feedback. This results in faster wet handling lap times on average compared to the RT43.

However, the difference in performance between the two tires is not markedly significant (especially after seeing how well the newer tire does in dry conditions).

In fact the predecessor Altimax RT43 shows up with slightly better wet braking. And that is due to the tire’s better optimized central siping having a curved (multi-angled) structure.

Unlike the sipes on the RT45, these are less prone to stiffening or closing up, especially during aggressive braking. And that closes in the performance gap here (well, for the most part).

But yes overall wet performance is still better on RT45 at the end of the day.

Hydroplaning

The ability to resist hydroplaning is an essential yet often underrated aspect of tire performance, especially crucial for maintaining control and contact with the ground.

But what is hydroplaning resistance exactly? Well it reflects the tire’s capacity to efficiently channel water away through its primary grooves.

And it gets measured by float speeds, indicating the maximum speed at which a tire can travel over water before losing contact with the road surface and beginning to hydroplane.

In this specific area, both the Altimax tires perform almost similarly, exhibiting nearly identical average curved and straight float speeds in tests.

Though if we’re splitting hairs, the older General Altimax RT43 exhibits a slight advantage in certain sizes that feature deeper tread depths. This greater tread depth allows the RT43 to displace a slightly larger volume of water, enhancing its hydroplaning resistance marginally in comparison to the RT45.

Snow and Ice Performance

Both the General tires here do not offer the 3-Peak Mountain Snowflake rating, yet they still are great for their all-season category.

But yes if winter performance is your priority, you should check out all-weather tires instead like the CrossClimate 2 or the the best rated in my top grand touring tires’ list, the Nokian SeasonProof.

Moving on…

So among the two tires here, the General Altimax RT45 emerges as the superior choice for snow conditions, outperforming in nearly all snow performance metrics comparatively.

And this advantage is largely attributed to its complex secondary groove patterns, which are designed not only for noise reduction but also for effective snow engagement.

These grooves play a crucial role in enhancing snow-to-snow contact, a key factor for traction in lighter, fluffier snow.

Why it matters? Well, because snow adheres better to itself than to rubber, giving the RT45 an advantage in such conditions over the RT43.

Additionally, the newer Altimax tire is equipped with more effective in-groove notches and a shoulder design featuring offset edges.

These features are adept at moving snow aside and provide greater propulsion in snowy conditions, or in other words, improved snow acceleration.

Noise Comfort

Tread noise primarily originates from air particles. They flow in to the tread, especially through the lateral gaps around the shoulders, and their collision (with the tread walls) generates pattern noise and in-groove resonance, resulting in vibrations.

Having said that, it explains the results from comparative tests where the Altimax RT43 is notably quieter. Its shoulder lugs are more compact, effectively limiting the entry of air and consequently reducing noise.

On the other hand, the General RT45, featuring a more open tread design, tends to be louder. Its structure permits more air circulation, leading to increased collisions and, subsequently, higher noise levels.

To Sum Things Up

In conclusion, both tires here have their distinct advantages.

The General Altimax RT43 leads in ride comfort, thanks to its dual-zone tread compound that better absorbs road imperfections, albeit with a trade-off in steering response.

On the other hand, the RT45 shines in fuel efficiency, aided by its stiffer rubber and lighter structure, and also demonstrates superior handling and traction in both dry and wet conditions, despite its slightly noisier ride due to its open tread design.

And yes the newer Altimax RT45 also takes the lead in snowy conditions thanks to its superior biting edges. Overall its a nice upgrade to have for sure.

If you have any questions or need more insights about these two tires, feel free to ask!