How fast can I go in LOW range???

[jmrivera]

Hi all,

I have a '03 Discovery HSE7 (4.6L, SLS, ACE) and for the life of me, I cannot seem to find a maximum speed rating in low range in my Owner's Manual. So, what is the maximum speed I can go in low range? I'm thinking 40 mph - is this too fast?

Thanks,
Jonathan

[Disco Mike]

Depends on how fast you want to blow up your engine!!
Why would you want to be reveing the high off road?
Mike

[jmrivera]

It's for towing a travel trailer... My plan is to tow in high range while I'm on the "major" thoroughfares and when I reach the mountain roads, I would shift into low for better control... However, I want to be sure that I do not damage anything by going too fast....

Will the rpm's and the engine let me know if I am going too fast???

Jonathan

[auwesman]

When you hit about 35 mph....you'll want to slow down
Low range will really tax your engine and is generally used for short periods, not for an extended amount of time.

[Disco Mike]

How heavy is the trailer?
You would be better off staying in high range and using 2nd. or 3rd. gear depending on the load.

Mike

[R_Lefebvre]

Yeah, the low range is really very low in these. I wouldn't use low range unless you're towing a REALLY heavy trailer up a long steep incline. Put it in low, tow slowly up the hill, take it easy and go slow, then put it back in high range when you're at the top.

Whatever the top speed is doesn't matter. I wouldn't sustain more than 3-4000rpm for a long time. That's only going to get you... I dunno, 25mph? Just my personal feelings on that.

If you're towing up something that steep, and want to go that slow, if it's not a 4 lane road, you're going to piss off a lot of people stuck behind you.

How heavy is the trailer? If it's not more than 5000lbs, I'd just leave it in high range, make sure the trans is in 3rd, and just take it easy. The important thing is you just don't want to be higher than half throttle for a long time. It's hard on the engine, and really heats up the trans fluid. If you're needing more than 1/2 throttle to go up at 30-40mph, it's slow down and then drop into low range and keep the speeds even lower. Again, you'd have to be towing a HELL of a load for this.

It's just something you have to feel out.

Edit: Yeah, I agree with Mike, even using 2nd in high range and going slow makes more sense than dropping it down to low range. And watch your gauges for overheat. I believe there is a trans temp sensor that will trip a light, Mike? If the engine is overheating, stop IMMEDIATELY, soon as it safe that you won't get killed. If you overheat this motor, you will ruin it.

[auwesman]

Have you had it in Low Range yet? If not, take it out for a spin around the neighborhood (again...not for an extended amount of time) without the trailer on it, put it in low and you'll be able to tell quickly she's not going to go very fast...nor should she. Driving it in low yourself will give you the best indication of when you should an shouldn't use it.

High range is very capable, so keep that in mind while towing and good luck with your trip! What mountain range are you headed too?

[jmrivera]

It's going to be around 5000lbs. and I'm planning on going all over Northern New Mexico and Southern Colorado...

I've been doing some off-roading in low range and it really seemed like overkill, so I shifted back into high, but used a maximum of 3rd and the Disco. played with ease... I suppose I will have to use some educated trial and error to determine the safest way to tow and operate the truck...

Thanks for all the input.....

[Thor]

Have you looked into the High Desert Rovers yet?

Southwest Rovers is owned by Rob Dassler, he's a great mechanic down your way.

Todd

[RudemanRB]

you'll be fine in High and 2 or 3rd gear. if your traversing hills. you might want to use Low but again. key is understand the terrain before you go. in most cases if you can. get out and walk your trail, or atleast get out and visualize your route before you just drive it.

good luck

Rudy

[mudmonkey]

5,000lbs should be an easy pull- I pull tractors and dump trucks every now and then on a trailer.
From memory (and that's not what it used to be) but doesn't it say somewhere in the owners manual about trying to stay above 20mph when towing heavy loads to avoid damage to the transmission, therefore I guess if the road doesn't allow for 20mph, you might want to change to low.

[ArmyRover]

I pulled a ML320 and a tandem axle car trailer through the kanagmangis pass in the white mountains in high range no issues. I didn't really push it but average speed was around 45-50. I'm sure I was over 5000 pounds and probably abusing the rover with that load but I needed to get her home to fix it so I didn't have to pay the obscene prices at a MB dealership.