Fuel and horses – Wrangler's new engine

Probably the most anticipated change to the Jeep Wrangler since the introduction of the current JK was the new Pentastar 3.6 litre V6 engine. Chrysler's new "hero" V6 will be widely used across its product range. 4wdNewz has already tried the Pentastar in the Grand Cherokee and Dodge Journey. It endowed the big Jeep with performance not much different from the Hemi V8, an impressive accomplishment. I've now had a chance to drive a Pentastar-powered Wrangler Unlimited on- and off the road. Although it's a good engine, I'm not sure it deserves the rapturous publicity afforded it by Jeep publicists and some motoring writers.

It all fits nicely, but there's not much spare room.
Note the air intake lower centre.

The new motor produces some 40 per cent more power, at 209kW, than the outgoing 3.8, but torque is up by only about 10 per cent to 347Nm, which is really neither here nor there. I was expecting the new Wrangler to really bolt, given all those extra kWs, but although it's undeniably quicker, it's nowhere near as "quicker" as the 40 per cent figure suggests. On the road, it knocks a couple of seconds off the 0-100km/h time, but when you think about it, that's not really a lot: "One-Mississippi, two-Mississippi." That's all. More usefully, its overtaking times are better, a safety enhancement. Driving some of the new tracks at the Jeep Woodhill 4WD Adventure Park I found no off-road advantage compared to the 3.8 in my two-door Rubicon. Except for one thing:

14.8 overall, including off roading!

As part of the package, the Pentastar comes with a new five-speed automatic transmission. This adds a ratio over the old box and manual tiptronic-type changing for when that's an advantage. This engine and gearbox combo provide outstanding fuel consumption compared to the outgoing model. After a session in low range, my 3.8/four-speed would be recording something like 19 litres per 100km, maybe more. After what I considered a reasonably hard workout, the Pentastar would do no worse than 16.5! This advantage is also apparent on-road, where it routinely saves around 2.5 litres per 100km compared to my 3.8 JK, despite the two-door being lighter than the Unlimited.

Happy in my ignorance

As the owner of a 3.8 litre Wrangler (see above item),  I’ve been following with interest overseas reports of the 3.6 litre Pentastar model since it appeared in August. Apart from its high fuel consumption I have had no problem at all with the old motor and quite liked the idea of buying one late in its production life when, surely, all the bugs will have been well worked out and when there is an aftermarket full of reasonably priced parts. True, the 3.8 has a humble background, developed more than 20 years ago primarily for minivans and people movers, but it worked quite well in the Jeep, where it replaced the bulletproof 4.0 straight six.

But almost universally, the early reports derided the outgoing motor. Its replacement was long overdue. It was wheezy, anaemic, underpowered, rough, dismal. One reviewer said that joining a freeway would no longer be a white-knuckle experience. And here I was thinking my JK joined the motorway flow very well. Too many motoring writers have a horrible habit of slagging an outgoing car or part of a car. Fair enough, I suppose, but where were their voices warning us what a load of crap we were driving, while the vehicle was still in production?

I’ve lived through this before. My Land Rover Defender was one of the last imported with the 300TDi engine. When the Td5 arrived, the earlier powerplant was derided as noisy, agricultural, underpowered, rough, unreliable and … you name it. In fact, the 300TDi is today often sought after by those who know Land Rovers. When the Td5 made way for the current Ford engine, the slaggers quickly jumped on it, of course. Land Cruiser owners had a taste of the same thing when the wonderful straight-six turbo diesel made way for the V8 diesel.  Both are worthy engines, but all of a sudden the six was “problem laden”, “clunky”, “too heavy for its output” and so on.

No wonder that journalists are down the bottom with car salesmen when jobs are ranked by public perception of the credibility and integrity of those doing them.

Something else sheep are good for

I'm quite keen on New Zealand-made Prolan as a corrosion inhibitor for the Jeep's chassis. It's made from wool grease and you'll find an earlier report here. The Tauranga based company has now developed a new product, Prolan Enduro, for under-chassis corrosion protection. It dries to a shiny finish and is said to be very durable. I've sprayed my chassis and will report back later. The fancy looking red and white nozzle is also new and seems to work just like the old one! I had a leaking problem with the old nozzle, so this might be the fix. By the way, those of us who use the lanolin product are in good company, the cranes and barges trying to get containers off the Rena are coated in the stuff. Here's Prolan's home page.