awg

well if thats what you want, sounds good to me...if I wanted to go 50, for instance, I would shuffle back & forth between 3rd and 4th, with the odd dab on the brakes
Just like a manual gearbox vehicle really, on the drive down from my rural property, there is many downhill, winding, tight dirt corners..I hurl my XJ thru them, and its important to have the RPM just right!

EZEARL

This stretch of road turns into 25mph 90 degree right and left hand curves at the bottom against a mountain with a concrete wall (there's a number of crosses on it where runaway trucks had brake failures over the years). For about 3/4 mile before that the speed limit drops to 40mph. LOTS of logging trucks heading to the mill coming off the mountain with a required speed limit of 10mph and using the lowest gear mandatory. Two mandatory truck pull offs for brake checks and one runaway ramp. So most of the time there's no use in being in a rush to get down to the bottom. Even if there's no truck traffic which is rare it's a rural area with not much traffic so no big hurry anyway.

dave1123

In my area of NY, US Route 20 runs east and west from Boston to Chicago and is like a roller coaster across the state. It runs thru every little rural town and village, up and down some of the worst hills in the state. It's only 2-lane blacktop and was built just after US Route 1 that goes from Bangor, Maine to Key West, Florida. Just 20 miles north of this is the NYS Thruway which follows the old Erie Canal route and is flat as far north as Lake Ontario. I live on top of a tall hill right in between the two locations. Every direction from my house is downhill! Now you can understand why I own jeeps! To make matters worst, I live in a "Snow Belt" which is just south of Syracuse and gets all the snow when the city gets missed. These hills can get really hairy with snow and ice, but we have some on the best snow removal crews around. I'm still thinking about a lunchbox locker in my rear diff!

I would like to say downshifting an automatic is actually helpful in extending the life of the clutches in it because it "wipes" the clutch plates in both directions, cleaning off any embedded debris. I got 253K miles out of my 42re in the WJ, which people say is the worst transmission Chrysler ever built, without any adjustments and regular fluid and filter changes. I only pulled it because I was swapping engines and thought it was about time for a fresh tranny as well.

EZEARL

"I'm still thinking about a lunchbox locker in my rear diff!"
This XJ is the only suv or truck,and most cars I've had that doesn't have a limited slip rear diff. No major problems but I can tell a difference in marginal traction situations.

There are certain trips I make fairly often where I run 3rd gear. Low speed limit roads (~35mph max) that have many curves,hills,and bad surfaces.

dave1123

Actually, because of the hills I run constantly, I run in 3rd gear for any speed up to 55 just so the engine doesn't lug trying to pull those hills in 4th lockup. 3rd lockup gets me 1800 to 2100 rpm depending on if it's locked up or not. I need a lunchbox because when delivering newspapers in the snow, I have to keep shifting into and out of 4wd to get out of the snow piles around the mailboxes. If I had both rear wheels driving, it would pull out in 2wd. Otherwise, I only use 4wd when I'm pushing snow while driving down the street. Even then, I have to shift out before doing a U-turn. I miss my 242!

kbeam418

One tactic I learned from driving truck for a living is called "snub braking" big trucks have to use this method or we'll smoke our brakes and have no brakes. You want to drop 5 mph in 3-5 seconds, gain 5 mph in no less than 10 seconds and repeat the process going down the grade. If I gain 5 mph in less than 10 seconds I drop another 5 mph until I stop gaining speed so fast. This allows the drums/discs and pads to stay relatively cool (they'll still be hot and you'll see the heat waves coming off the drums) and if you have to come to a complete stop you'll be able to. I do the same thing in my jeep and car and my brakes stay cool. The AMC 4.0 has excellent engine braking but the xj has small brakes, I use ceramic pads since they can take more heat plus I keep the revs above 2k. If you ride the brakes they WILL start to fade and if the grade is long enough they'll catch on fire.

Transmissions produce heat when they're shifting (and idling) so if you notice the transmission constantly shifting you want to put into 3rd or 1-2 if going slow enough. The aw4 is well designed and holds gears rather than shifting, it's shifting is mostly based on throttle position so if you are giving a what for it'll hold 3rd or even 2nd gear all the way to redline before it shifts. When going down a grade you want to keep the rpm between 2k-3k rpm for maximum engine braking, 3rd gear for highway speeds 1-2 for rural speeds.

jordan96xj

I do a lot of driving up and down 20 and off into the state forests in the hilly terrain. For any hills, and anything at 55mph and below - I am almost always in 3rd. As dave1123 said, left to its own devices, the XJ likes to shift into OD as low as 38mph, which means a lot of wasted gas and power when going up and down hills. You can force the down shift via the pedal, but just keeping it in 3rd works a lot nicer. On really long steady downhills I might manually shift back to D (4th/OD) so that the transmission braking disables. But if I'm on the brakes a lot, I'll keep it in 3rd.

dave1123

I just want to add that this is where the 42re shines! It is so controllable! In my 2000 WJ I just push the button on my shifter and it drops to 3rd gear and stays there. If that's not enough, pull the shifter back into 2nd. My XJ takes some getting used to. I tried an experiment yesterday that didn't work so well. I have a 20% grade (I think) that I travel quite often near my house and was going up it in 3rd gear waiting for it to downshift as it usually does, but pulled it back into 1-2. It instantly went to 1st, then shifted up to 2nd. Next time I'll just wait for it to do it's thing. It usually pulls that hill at 25-30 mph at around 2000 rpm with no problems if I just approach it in Drive. Coming down it is another story. 3rd gear isn't enough engine braking and I have to pulse the brakes to keep the speed below 35. It's narrow road with no centerline or shoulders thru the woods and many curves. I quite often meet another car coming the other way in the middle of the road! Also tractors pulling wagons or dump trucks!

downs

I went in and ground down the lock tab on the gate between D and 3 on my shifter assembly. This allows me to simply pull the shifter between D and 3 instead of having to push the button on the shifter and then pull. You don't have to grind it all the way down just enough to take the hard edge out of it and it will slip between the two gears. I like to run in 3rd in hilly terrain or areas where I'm going to be running under 45 mph for long periods of time I simply leave it in 3rd.