Climbing Hills 2000 xj command trac trans.

[longfellow]

Need some simple imput on gear use climbing hills that you may find in Pennsylvania . I do not mean off road type just your everyday highway
hills .
In 2h there,s 1/2,3,and D. Whats best to use for climbing extended steep highway hills.

I find that D setting has plenty of sufficient power and will downshift
when engine calls for it.

I feel that 3rd gear is ok for decending for mild speed control when comeing down hills.
What do u guys normally use in above mentioned questions on decending and climbing ? What,s best for Jeep to use to prevent stressing trans heat.

W hen taking off in drive when engine in Jeep is cold' why do these Jeeps have a power roar to them . Once eng. is warmed up, this condition gets quieter. Is it the way their geared or what.
later, Longfellow

[fredjacksonsan]

When going through the mountains on the highway and going uphill, I'll wait until the transmission shifts to 3rd by itself, then lock it in 3rd for the rest of the hill, and turn the o/d back on when at the top. On a major highway, I usually don't downshift on the downhill side, just take foot off the gas while in o/d.

Heat will build up from a lot of shifting, so that's why I lock it in 3rd going uphill - otherwise it will shift back and forth between 3rd and 4th.

If you're going down a twisty road that requires braking frequently, then it's a good idea to downshift and leave it there until it levels out.

It all depends...major highway like the turnpike or some twisty road with a speed limit of 40.

Don't know about the roar without some more information.

[longfellow]

Fred,
It,s just the way these Jeeps sound when u take off in cold motor settings. Seems you have to pick up on gas to get er rolling. After warm up this is less needed.

[AlohaBra]

Hey longfellow,

I am sure out there you will have a long stretch like we have down here in SoCal called the "gravevine", the I-5. When going up the grapevine which is steep, all the semis will be gearing down and the cars will be passing. This is like for 30 miles straight up. That is when you have to really step on it and the engine is trying to work hard. Here where you want to down shift your auto trans to help keep the engine temperature down. That to me is the real reason to downshift (it keeps the water pump going faster and the engine from lugging). You will often see cars overheating and pulled over on streches like this.

The reason to downshift going down is for safety, to keep from overheating your brakes or worse, warping the rotors. So downshift and enjoy the ride when you have to use your brakes more than 5 minutes or so at a stretch.

By the way, ALWAYS use an external trans cooler if yours didn't come with one. (Cost=$50)

[AlohaBra]

Roaring noise--
*For 30 seconds or so, the engine is in retard to help warm up the cats (the convertors), so that could be it
*The exhaust header is known to crack where the two goes into one and leaks there until heated up
*PS--I have heard so called roaring but never paid much attention to it, maybe you can find out by opening the hood and letting us know

Aloha and best regards...

[xj31]

The roaring noise might just be from the clutch fan.common on a lot of vehicles to make noise for about a city block or so.

[gtmud]

Long,

I myself am from PA and have an idea of the road conditions ( NW Pa). Like Fred siad, when your climbing long grades like that of the turnpike, wait for the tranny to down shift, then drop the selector into 3rd. You'll notice alot more power. I too had an 00 XJ and loved the turnpike, kick it down in 3rd and watch everyone you pass! As far as down shifting, I never had a need for it, even while in Vermont, just let your foot off the gas and the tranny will do the rest, also when you are braking, don't hold the pedal down for a long period, too much heat, let off occasionally to cool the rotors down. IF your worried about over heating the tranny, you can purchase an Aux cooler for the tranny, but its not really nessacary unless your towing. I would say though, while I was in Vermont, climbing the mountians ( highway) there, after a while the mechanical fan clutch was engaged somuch that I could notice the lack of power. If you want look into replacing the mech. fan with an electric using an adjustable T-stat. It will save you a little gas and give you the extra power you need when climbing steep grades like those around Kinzua Dam and Jake's Rocks.

[AlohaBra]

Originally Posted by xj31

The roaring noise might just be from the clutch fan.common on a lot of vehicles to make noise for about a city block or so.

It does sound like the clutch fan...good point.

[neon_rt]

My fan roars in the morning for a while. In the morning I usually start the engine, let it run for a few seconds, rev it to about 2000 rpm (while the fan roars) for a few seconds until the fan quit roaring, then I put it in gear and drive. I don't like listening to the fan roar while I drive. The ultimate fix for the fan roar is to replace the mechanical fan with an electric. I plan on doing that sometime next summer.