Playskool JK StewingRegarding “All-New Jeep JL Wrangler” (Apr. ’18), I take offense to you calling my new JK interior as being “Playskool.” Now that there is a newer Wrangler model, it does not mean that the older ones are pieces of junk! I would expect more from a contributor to a Jeep magazine criticizing a current product of Jeep.
Sorry if we ruffled your feathers. We meant no offense. However, when you compare the fit, finish, styling, and comfort of the new JL interior to the outgoing JK model, it does leave you somewhat amazed at how much better the new Jeep is. Of course, we understand that no one wants to think that their Jeep is inferior. In all honesty, the Jeep JK is still a great Jeep, and far better than many previous models before it. It’s just that you can’t deny that the JL is an improvement on the JK, and rightfully so. It should be a better Wrangler than the outgoing model, don’t you think? It would be extremely unfortunate if Jeep were to go backward in Wrangler advancements. We embrace all Jeep models, but we’ll also lay out the truth about each model and make logical comparisons for the readers to understand the changes and advancements that come with each new Jeep.
Engine Mix-UpSince I'm an AMC fan, I feel like I should tell you this. The 232 and 258 engines got a bellhousing pattern change for 1972, making it the same as the AMC V-8. I found this out the hard way. The Buick 225 V-6 also had a bellhousing change in 1964 to the standard BOP pattern. This guy I used to know had a real early-’60s Buick with the 225 V-6 in it. GM had this engine on paper in the late ’50s. I had worked in a car repair shop for 18 years and have seen some weird Jeeps. One guy allegedly ordered a brand-new Jeep pickup with a 304 IHC in it! Another guy allegedly ordered a Jeep pickup with a Pontiac 350 in it! I did work on both of them.
The very first time I saw the words "All-Wheel Drive" was on a Jeep pickup back in the ’60s. Why didn't Jeep copyright that term?
There may have been some sort of mix-up or misunderstanding with the owners of those Jeep trucks. The International Harvester 304ci V-8 was never available in the Jeep pickup. However, the AMC 304ci V-8 debuted in ’71-model Jeep pickup trucks, among other Jeep models. Many people mistakenly think the AMC and IH 304 V-8s are the same engine, which they are not. The only thing they have in common is displacement. As for the 350ci engine, that would be a Buick V-8. It was named the Dauntless V-8 under the Jeep brand. The Buick-sourced engine came online in the Jeep trucks in 1968.
Now, it is possible that someone may have swapped an International Harvester 304 and a Pontiac 350 under the hoods of the trucks you worked on, although it isn’t very likely. Neither of these engines have been popular swaps for Jeeps in the past nor present.
3.8L ClarificationsThe “Lowdown on Jeep Six-Shooters” (Apr. ’18) article is very interesting, thank you. I have a ’08 four-door Jeep JK Rubicon. I did not realize the poor performance of the 3.8L until I installed 35-inch tires.
I have a couple of questions regarding the 3.8L. You mentioned that installing any power-adding items is asking for trouble. What power-adder items are you referring to? I’m very much interested in an engine swap. My concern is meeting the emissions standards for a state like Utah when installing an LS or a Hemi V-8?
Thanks again for the article and your insight.
Trent McGee replies:
Thanks and I’m glad you enjoyed the article! The 3.8L isn't a bad engine per se, it’s just not a great one. Much like the minivans that they primarily powered, the 3.8L is adequate for the job but entirely unremarkable. By power-adders, I was referring mostly to forced induction. Unlike the Pentastar, the bottom end of the 3.8L was never designed or intended for use with a turbocharger or supercharger. There are kits that exist to add that stuff to a 3.8L, but reliability suffers. It’s pretty well proven that 3.8L engines don’t deal with hard use very well, and forced induction just places more strain on already marginal internals. It’s my opinion, and that of many others. Trying to wake up the 3.8L is filled with potential pitfalls. Things like headers and a cold-air intake certainly don't hurt, but I personally haven't noticed much of a gain adding that stuff as you do on some other engines. The bottom line is this: treat it nicely and maintain it, and it'll probably go 200,000 miles or more. Beat on it a lot or throw a supercharger on it, and don't be surprised if you end up with holes in the block where they don't belong.
As for engine swaps, both Hemi and LS swaps are well documented and supported. LS engines are physically smaller and therefore a bit easier to place in a JK engine compartment, but both are very viable options and can endure a lot of abuse without much issue. I'm not intimately familiar with Utah emissions and therefore can't speak intelligently on what may or may not fly. I would recommend talking to a local shop that has done a few swaps and see what they say. If you're in the Salt Lake area, talk to John over at Impulse Off Road (impulseoffroad.com). He's a good guy and could probably help you weigh your options for Utah emissions.
I hope this helps, and good luck with your Jeep project!
Dishonorable Six?I love the magazine. In “Lowdown on Jeep Six-Shooters” (Apr. ’18) you nominate the Buick 231 V-6 for an honorable mention. You are right by stating these engines litter junkyards. They are junk! The engine is a bad design from the factory. The oil pump is located next to the harmonic balancer and not in the oil pan. Because of this, the oil pressure takes longer to build up after starting. The first things to go are the cam bearings. My wife had a ’83 Buick Regal with this engine and it chronically had low oil pressure. I was able to nurse the engine to 75,000 miles using synthetic oil, thereby keeping some oil pressure. The main bearings finally went. Looking around in local junkyards I have found that all of the vehicles that had this engine only had between 50,000 and 65,000 miles on the odometer. Do your readers a favor and make the Buick 231 V-6 a dishonorable mention.
Cross-Country RecountReading Trail Head (May ’18) brought back an awesome Jeep memory for me. It was the summer of 1996, my friend Bill and I had some mildly outfitted Jeep XJs. We decided to load up his ’87 XJ Pioneer sporting a Tomken Machine 6-inch lift, 33-inch BFG Muds, 4.56 gears, ARB Air Lockers, Tomken bumpers and tire carrier, and a Con-Ferr safari rack. We headed west from southeast Pennsylvania. We drove on a mission-like timeline and pulled into Moab on the third day of driving. We spotted another lifted XJ in town at the local mountain bike shop and introduced ourselves. I can't remember his name, but he took us out for a day of wheeling. A few days later we loaded up again and headed to Lake Tahoe. We hit the Rubicon Trail a couple days later. Luckily it was a Sunday and a small group from a local club was heading out from a weekend of camping. I say lucky because our Jeep was not dealing so well with the altitude changes and we were having issues with oxygen sensors. The Jeep wouldn't run and those guys strapped us off of the trail. One of the guys had a real nice flatfender and tried to drive up a tree. He put it on its side, so we all gave a hand and got it back on all fours. We limped the XJ up to Idaho Falls and had new sensors put in, then headed east. We hit up Yellowstone on the way back to Pennsylvania and racked up about 6,700 miles round-trip. Even though we didn’t accrue a ton of dirt miles, I have a ton of good memories. Twenty-something years later we are still the best of friends and have each had a long list of Jeeps.
Take care and safe travels!
Manual vs. AutomaticThanks for publishing my letter (Mailbag, Apr. ’18). I totally agree (sad to say) about the unpopularity of manual transmissions. In regards to the reliability/durability part I have to respectfully disagree. I realize that people with a lack of knowledge or who are abusive can shock load a manual transmission–equipped driveline. There is no torque converter to protect the vehicle from them as there is with an automatic. Thus, the reason to use detuned engines to preserve the drivetrain. Having said that, look no further than Jp a few years ago about automatics versus manuals. The article spoke to having to beat shoe leather when an automatic was bashed on a rock and lost fluid. A manual can most likely be limped home per the article.
Personally, I have owned a good number of manual transmission–equipped vehicles. Everything from cars to 10-wheel tractors. I’ve never had trouble with any of my manual transmissions, and only ever replaced one clutch (in a car where the rear engine seal went and oil soaked said clutch). I've only owned one automatic, in a Chrysler van. Despite regular maintenance, it eventually needed to be rebuilt.
Folks looking for that automatic experience should be in for a treat in the future. Self-driving Jeeps will take them over the trail of their choice, while they sit in the passenger seat and take photos. I hope that my manual-equipped ’02 SE outlives me.
The manual versus automatic transmission debate has always been and still is a constant ongoing battle with fewer and fewer manual transmission supporters every year. Don’t get us wrong, we love our manual transmissions, but automatic transmissions have their place too.
In all actuality, it’s very likely that future automatic transmissions will fundamentally be more like manual transmissions, but with dual-disc clutches and electronic shifting mechanisms. Today’s common fluid-coupler–style automatic transmissions just aren’t all that efficient. There are probably some fuel economy gains left on the table that could be attained with a manual automatic as the technology becomes more affordable. These manual-automatic transmissions are already out there in several high-volume production cars.
Backflow BrakingI’m going to challenge your brake residual pressure valve explanation (Your Jeep, May ’18) regarding the small residual pressure in the brake lines of drum brakes. I'm sure we were told in school in my apprentice days 50-plus years ago that pressure was to keep the cylinder cups sufficiently seated so as not to leak. The star wheel adjuster keeps the shoes up close to the drum. The return springs are strong enough to overcome that minimal line pressure. That’s my story and I'm sticking to it.
Love your tech stuff, even as a nitpicker.
Vancouver Island, British Columbia
You’re right! While it is true that the drum brake shoes are held in place close to the drum braking surface with the adjuster assemblies, the wheel cylinder pistons and plungers can still retract away from the shoes. The residual pressure valve in a drum brake system is used to keep the wheel cylinder pistons from working their way back into their bores when the brake pedal is released. A small amount of line pressure (around 10 psi) allows the wheel cylinder plungers to maintain contact against the shoes in the drums. This provides much quicker drum brake engagement when the brakes are applied and reduces brake pedal travel.