What lessons learned did Jeep incorporate on each generation going forward from the TJ?

[hear]

Jeep quality has never really been a hallmark. I remember hearing that back when the TJ's were still in production. But having had several TJs and a JKU, I can attest that engine-related stuff and the excess electronics are issue-prone. And hard to troubleshoot, since there isn't (yet) a large community of DIYers there yet. Just pop into the JK forum here. It's pretty quiet compared to this forum, and the depth of expertise is just not there.

But the creature comforts are great. Most of us don't drive a jeep for comfort, but as much as I love driving my TJ, my JK was a better ride overall.

 

[GATORB8]

Nice data sheet!

Smaller ring gear (8.99 vs 8.66) moves pinion offset 0.12 inches or 3 mm. That means the pinion has lost 15mm of "lever arm" (18.1mm-3mm of offset from ring gear diameter difference) meaning pinion must apply more thrust to achieve same torque on carrier...angular ball bearings will never take the abuse tapered roller bearings will either. Maybe there is a correlation with people having pinion failures in JL axles? I really think the JK axles were peak for Jeep.

Nice to see they beefed up the front tubes and kept the rears the same.

I certainly won't pretend to be an R&P expert. Reading, it looks like there were some additional modifications to both the size of the pinion shank and to the cut (shallower but with extended contact) that supposedly net to a stronger set.

IIRC, JT, 392, XR, and 4xes all have stepped up tube thickness to ~3/8 from 1/4 over the changes in the diagrams.

From a early JL Northridge writeup, this is a front 5.38 43-8 set for JK (left) and JL (right):

 

[InOmaha]

They added 2 extra doors so more people would buy them. Dad's who needed kid seats so he didn't have to drive a minivan and soccer mom's who wanted something smaller than an F150.

A lot of TJs go for sale with the line, "Had kids and need something bigger".

My brother built a 4 door one up. It's longer wheelbase and wider stance makes it comfortable to ride in. It's quieter inside. He gets about the same mpg as I do. His gas tank location causes a lean to one side when it's full. His armor plating underneath was more complicated.

The rest of the stuff they put on just costs money. Anyone with money can add heated seats, entertainment centers, remote start, automatic door locks/windows, outboarded shocks, gearing, axles, tires, etc to a TJ and probably come in at or under the price of a new Jeep.

All TJs should have been LJ Rubicons.

 

[Chris]

The nice thing about TJs too is they've been around long enough that all of their problems and quirks are well known and mostly easy to fix.

I'm thinking of the rear main seal, PCM issues, OPDA issues, and maybe a few others. Easy stuff though in comparison to what you're going to deal with on a JK or JL.

 

[InOmaha]

Maybe blow the sand off the engine castings would be good lesson learned.

https://www.thedrive.com/news/stell...13000-jeeps-over-self-destructing-turbo-fours

 

[Longwhitejeep]

The nice thing about TJs too is they've been around long enough that all of their problems and quirks are well known and mostly easy to fix.

I'm thinking of the rear main seal, PCM issues, OPDA issues, and maybe a few others. Easy stuff though in comparison to what you're going to deal with on a JK or JL.

Lots of articles and videos in the past few years mentioning the TJ as the last true JEEP


https://www.hagerty.com/media/car-profiles/why-jeep-wrangler-tj-is-best/

https://www.motortrend.com/how-to/154-1211-last-real-jeep

https://www.topspeed.com/why-the-tj-is-still-the-best-wrangler-to-date/

 

[Chris]

Lots of articles and videos in the past few years mentioning the TJ as the last true JEEP

IMHO I believe it is.

It's certainly the last of the Wrangler platform in which it's possible (and rather easy) to work on yourself.

The same cannot be said for the JK onwards. Obviously we're all biased (this is a TJ forum after all), but the TJ platform is very simple compared to the generations that succeeded it.

 

[Longwhitejeep]

I think one improvement is the closer to flat belly on the jk and up from the factory.

Shock placement has been mentioned I think.

Hard top removable panels would be sweet on any year jeep.

I also saw this article this morning. Seems bronco is taking a lot of market share lately.

https://www.thedrive.com/news/ford-...e-jeep-wranglers-dominance-for-the-first-time

 

[hear]

It's certainly the last of the Wrangler platform in which it's possible (and rather easy) to work on yourself.

The same cannot be said for the JK onwards.

I had to replace the oil pump on my JK (3.6L). First I had to take off the lower oil pan which was bolted and RTV'd on. Then I had to remove the upper pan, which was bolted and GLUED on. You have to literally get a prybar in the wheel well to get it off. Took a LONG time. And to change the oil pump you have to take off the lower timing sprocket and fish the solenoid connector through a tiny hole on the back side. Nearly impossible.

What's that? It didn't clear your P06DD? Oh, now you have to go up top, drain the coolant, remove both layers of intake, pump/dry out the valley, replace the oil cooler & pressure sensor, then put it back together. And then re-fill the coolant and pray you can sell it before the P06DD comes back on.

 

[jeepguy03]

I think one improvement is the closer to flat belly on the jk and up from the factory.

Shock placement has been mentioned I think.

Hard top removable panels would be sweet on any year jeep.

I also saw this article this morning. Seems bronco is taking a lot of market share lately.

https://www.thedrive.com/news/ford-...e-jeep-wranglers-dominance-for-the-first-time

The bronco is a cool idea, but it's still a modern vehicle, and one with Ford problems. I have two coworkers with them. One is on her THIRD one after Ford couldn't resolve the issues on the other two, and the other coworker complains about the transmission and water leaks in hers.

 

[Chris]

I had to replace the oil pump on my JK (3.6L). First I had to take off the lower oil pan which was bolted and RTV'd on. Then I had to remove the upper pan, which was bolted and GLUED on. You have to literally get a prybar in the wheel well to get it off. Took a LONG time. And to change the oil pump you have to take off the lower timing sprocket and fish the solenoid connector through a tiny hole on the back side. Nearly impossible.

What's that? It didn't clear your P06DD? Oh, now you have to go up top, drain the coolant, remove both layers of intake, pump/dry out the valley, replace the oil cooler & pressure sensor, then put it back together. And then re-fill the coolant and pray you can sell it before the P06DD comes back on.

And while you're in there on the top end you may as well replace the oil cooler as well since we know how prone those are to failure.

Also, carry a spare TIPM since those seem to go haywire all the time.

There is no doubt in my mind that the JKs and JLs (I owned a JK) drive better than the TJs (mostly due to the longer wheelbase and more power), but they're unnecessarily complicated and a pain in the butt to work on.

 

[Chris]

The bronco is a cool idea, but it's still a modern vehicle, and one with Ford problems. I have two coworkers with them. One is on her THIRD one after Ford couldn't resolve the issues on the other two, and the other coworker complains about the transmission and water leaks in hers.

Take it from someone who owns a new Ford, don't ever buy a new Ford. Actually, just don't buy any modern vehicle unless you can afford to lease.

 

[hear]

Take it from someone who owns a new Ford, don't ever buy a new Ford. Actually, just don't buy any modern vehicle unless you can afford to lease.

Had to trade our 2020 Expedition because of a known flaw in the transmission that Ford has since re-designed but refuses to recall. $11k for Ford to fix, $5k for me to attempt to rebuild/upgrade, but no more warranty + who knows the level of difficulty of removing the unit. I decided it was better to limp it to the Hyundai dealer while I still could. Hoping the 100k warranty isn't a scam. We put too many miles on to make leasing practical, plus my kids are licensed professionals at destroying a vehicle interior.

 

[jeepguy03]

The stories from my friend who was a service advisor strengthened my theory that most people are drowning in debt. I'm a weirdo car guy who researches everything and isn't afraid to swap a transmission in my garage or plug a laptop into my car, I have no idea how everyday "normal" people afford modern vehicles and the 5 digit repairs they require like a new engine/turbo on a run of the mill Ford Escape appliance-box that is barely out of warranty. I remember asking him about the 3.5L Ecoboost being a good engine, and he laughed and said they had 60 F150s on the lot waiting on replacement 3.5 Ecoboosts under warranty.

 

[Chris]

Had to trade our 2020 Expedition because of a known flaw in the transmission that Ford has since re-designed but refuses to recall. $11k for Ford to fix, $5k for me to attempt to rebuild/upgrade, but no more warranty + who knows the level of difficulty of removing the unit. I decided it was better to limp it to the Hyundai dealer while I still could. Hoping the 100k warranty isn't a scam. We put too many miles on to make leasing practical, plus my kids are licensed professionals at destroying a vehicle interior.

Yep, I've been going through transmission woes with the 10R80 in my 2019 F150. Back in 2014 when we had a new Ford Focus at the time I dealt with a slew of transmission problems with that thing as well. Ford wants $9000 for a new 10R80 transmission including labor. No way I would dump 9k into a vehicle only to have the transmission fail again in 80k miles.

Ford couldn't build a good transmission if their company depended on it. I thought it was just Ford, but the more research I did, the more I realized that this isn't just a Ford problem, it's all modern vehicles. The transmissions are electronically controlled pieces of crap. They (like everything else) are built to be disposed of once they fail, not rebuilt.

Speaking of the kid thing, that's another reason we won't buy a new vehicle. Any vehicle you buy, my kids will trash the interior within a short period of time. They know better than to do that with my vehicle though. Somehow my wife lets them get away with it.

 

[Chris]

The stories from my friend who was a service advisor strengthened my theory that most people are drowning in debt. I'm a weirdo car guy who researches everything and isn't afraid to swap a transmission in my garage or plug a laptop into my car, I have no idea how everyday "normal" people afford modern vehicles and the 5 digit repairs they require like a new engine/turbo on a run of the mill Ford Escape appliance-box that is barely out of warranty. I remember asking him about the 3.5L Ecoboost being a good engine, and he laughed and said they had 60 F150s on the lot waiting on replacement 3.5 Ecoboosts under warranty.

Which is too bad because I will say that I LOVE the 3.5 Ecoboost in my 2019 F150. It's got gobs of power and it's so smooth. Unfortunately they have all sorts of issues. Mine currently has the cam phaser issue (another Ford problem). Supposedly it's 13-15 hours of labor and requires tearing apart a good chunk of the engine.

I'm to the point in my life now where I've learned that I will no longer buy vehicles I cannot work on. My F150 was the final mistake (which is why I am replacing it with my K10). After this I am no longer buying anything unless it's something I feel comfortable enough to sit in my shop and drop the transmission, as you said. Finding a good mechanic is nearly impossible these days. It's going to become even more difficult as our population (and our civilization) collapses around us. The really tradesmen are becoming more-and-more scarce these days.

My recommendation is to learn to work on your vehicle yourself, as least as much as you can. It's a skill you'll be thankful to have in time.

 

[Irun]

I think one improvement is the closer to flat belly on the jk and up from the factory.

Shock placement has been mentioned I think.

Hard top removable panels would be sweet on any year jeep.

I also saw this article this morning. Seems bronco is taking a lot of market share lately.

https://www.thedrive.com/news/ford-...e-jeep-wranglers-dominance-for-the-first-time

I see more and more Broncos. Hard to deny they nailed the body style.

 

[Rickyd]

Jeep quality has never really been a hallmark. I remember hearing that back when the TJ's were still in production. But having had several TJs and a JKU, I can attest that engine-related stuff and the excess electronics are issue-prone. And hard to troubleshoot, since there isn't (yet) a large community of DIYers there yet. Just pop into the JK forum here. It's pretty quiet compared to this forum, and the depth of expertise is just not there.

But the creature comforts are great. Most of us don't drive a jeep for comfort, but as much as I love driving my TJ, my JK was a better ride overall.

I really like just how quiet a stock 3.6l jk is compared to a stock 4.0l tj. They creep right along in the woods.

Even with a stock exhaust and cat,my 4.6l stroker is much louder. That's ok though. It just means if i want to get a bunch of pigs i need to haul ass and bring my 300blk ar15

The supersonic rounds do pretty well

 

[Longwhitejeep]

The bronco is a cool idea, but it's still a modern vehicle, and one with Ford problems. I have two coworkers with them. One is on her THIRD one after Ford couldn't resolve the issues on the other two, and the other coworker complains about the transmission and water leaks in hers.

So not much different than the new jeep alternative really. I think it comes down to on road comfort. Most people aren’t really wheeling these things.

Take it from someone who owns a new Ford, don't ever buy a new Ford. Actually, just don't buy any modern vehicle unless you can afford to lease.

I think the sweet spot for modern vehicles and reliability is early 2000’s into mid/late teens. The latter being more model dependent. My 11 tundra has been absolutely trouble for 10 years and 160k.

 

[RangerTJ]

Maybe blow the sand off the engine castings would be good lesson learned.

https://www.thedrive.com/news/stell...13000-jeeps-over-self-destructing-turbo-fours

My 2017 JK had the casting sand issue.

The coolant overflow bottle had a few inches of sludge in it at 10k miles.

You would think that Jeep would have learned by now that sand + engine = no bueno.