Using cruise while towing???

Expidia

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I'm trying to squeeze this season out of my Saab 9-5 while towing my less than 1000 lb aluminum rig. I've managed to get two seasons so far. Odddometer just turned 124k.
I'm going to move up to an SUV, hopefully by next season.

My question is when I take my 2.5 hour one way to the lake up north and back is it better for the transmission that I don't use cruise?

I tend to drop it down into third gear (it's an auto) when approaching long uphill climbs as the highway winds through the mountains thinking that the lower gear will take some stress off the tranny. But I've been avoiding using cruise anymore while towiing due to the mileage, small car for towing and a tranny with 124k on it.

Maybe using cruise is actually better for the tranny? This is why I'm asking the question.
 

This_lil_fishy

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Re: Using cruise while towing???

Outside of the safety factor, I don't think it would do any harm, depending on how the ECM is programmed. I know my truck will hold a gear longer when it climbs a hill in cruise, and will only upshift after the load is over. We have a nasty climb close to home we call the tranny killer, so that's what I have experienced. I've never used cruise when towing though, as I like to vary my speed according to road conditions, and climbing a hill is one of those conditions that I slow down for, as it is a strain on all of the drive components...in particular the cooling system.

Ian
 

clarkbre

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Re: Using cruise while towing???

I generally try to use cruise as much as possible because it is consistent. I have a Subaru Legacy that I tow a 1000 pound set up with. However, I always have it out of overdrive and keep it in 3rd.

My theory behind using cruise is simple: the tranny will stay in the same gear longer. By driving without cruise you're putting undue stress on the tranny by always speeding up or slowing down. The constant change in RPM's and power of the engine makes the tranny shift much more than it would if it were set on cruise control. With cruise, on mostly level roads or highways, the vehicle will just go on it's own and keep consistent.
 

nlain

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Re: Using cruise while towing???

I am in the flat lands of the South with some rolling hills, I just went to central Florida and on the interstate and open secondary roads I used cruise, when I got in heavy traffic or in towns no cruise, I am over 200,000 on mine.
 

daman4469

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Re: Using cruise while towing???

As a rule of thumb, cruise should not be used, towing or not towing, anywhere except on the highway. Cruise makes use of all the gears, and constant shifting on hills, especially when towing, is never good. I do use cruise when on the highway....I realized that it doesnt really work that well anyway in hilly terrain...youre better off using your foot to keep your speed up.
 

JB

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Re: Using cruise while towing???

There is no "one size fits all" rule for this.

Read the Owner's Manual. A change in final drive ratio can make a big difference

If the tranny "searches" on grades, avoid OD. If it pulls grades in OD without loss of rpm or rise in temp it is probably okay to tow in OD.

My V6 Ranger would struggle on grades in 5th towing 1200# but my V6 ML320 cruised the same grades in 5th towing 3,000#
 

Expidia

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Re: Using cruise while towing???

Thanks for the replies. I figured the tranny changes gears more when on cruise. I can't remember because I don't use it anymore while towing because the car has so many miles on it.

But I wondered about starting to use it again now that i'm doing 2.5 hour trips each way. I guess I'll just try it again on long flat stretches and watch the temp and beware if it's shifting too much. The trip from Albany to lake champlain is all highway but as I get farther north it has long stretches of gradual climbs as the road passes through the mountains.

I'd hate to have to spring for $3500 for another tranny if I can sqeeze this upcoming season out of it.
 

nlain

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Re: Using cruise while towing???

I will add that when I pulled my boat North and got into some good hills where the trans started to hunt then I shifted to direct, OD is plenty strong enough to haul the load it is the constant upshift/downshift that kills the trans.
 

windsors03cobra

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Re: Using cruise while towing???

You seem worried about the trans yet you tow in overdrive, I would say do just what ya been doing cause the car is still going.

124k miles is pretty young car still, plenty of life left in most cars @ 124k. Getting a new ride is fun tho, I think I want a Lincoln MKX or Mark LT next. :cool:
 

Expidia

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Re: Using cruise while towing???

You seem worried about the trans yet you tow in overdrive, I would say do just what ya been doing cause the car is still going.

124k miles is pretty young car still, plenty of life left in most cars @ 124k. Getting a new ride is fun tho, I think I want a Lincoln MKX or Mark LT next. :cool:

Where else would I tow with an automatic? When I'm in drive I guess it goes into overdrive if not under a strain? I drive in 3rd when I'm going up a hill. It's not a standard. I have no control of overdrive unless I drop it down to 3rd. I didn't think winding in 3rd gear was good for it over the long haul. I don't know. I'm not a car mechanic!

I love the car but I'm going to need the SUV to pull a 22 foot 3500 lbs of baot and motor plus the weight of the trailer. I had originally planned to go 200k with this car.
 

Expidia

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Re: Using cruise while towing???

I will add that when I pulled my boat North and got into some good hills where the trans started to hunt then I shifted to direct, OD is plenty strong enough to haul the load it is the constant upshift/downshift that kills the trans.

Thx, I usually drop it down to third more to save on gas. I don't get much of a strain cause the load is less than 1000 lbs. If I had 3 more people in the car it would be around 600 lbs anyway, so I don't think it's a big deal for the Saab to pull the trailer.

I don't find the tranny up or down shifting that much. Goes to overdrive pretty quickly and stays there on the highway.
 

Silvertip

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Re: Using cruise while towing???

The issue with using cruise control for towing is that it does not "anticipate" very well. In other words a slight grade generally poses no serious issues but going downhill through a gully and then suddenly up a steeper grade causes the cruise control to apply throttle in ever increasing amounts finally the ECM realizes a downshift is necessary so the whole system sort of overreacts. My technique is to use cruise, provided the tranny does not spend a lot of time hunting (up/down shifting -- or torque converter unlocking/locking). When I approach a hill, I will simply add a bit of throttle (step on the gas a bit) to increase the speed before the hill begins slowing you down. About halfway to the crest you can begin letting off the gas to let cruise regain the preset speed. Unless the hill is really steep the tranny will not unlock the torque converter. The caviat here is everyone drives differently, tows a different load, with a multitude of different vehicles all of which have different towing characteristics. But in the end -- anticipating a hill will generally result in less converter activity and fewer downshifts.
 

seaman campbell

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Re: Using cruise while towing???

The issue with using cruise control for towing is that it does not "anticipate" very well....
....anticipating a hill will generally result in less converter activity and fewer downshifts.

The exact point that needed to be made. I tow in OD i do not use the cruise because it constantly searches for gears while on a grade, I keep the OD engaged and manage the fuel so the tranny does not shift to third. I generally run around 1450 rpms @ 55mph great fuel saver with a 360CID motor.

TC
 

Expidia

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Re: Using cruise while towing???

Thx for the replies. I'll try the cruise again this coming weekend will do another 2.5 hour trip up North. But with a little assist to keep it from shifting when I come up to the upgrades.
 

clarkbre

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Re: Using cruise while towing???

The cruise control is a moot point. It doesn't matter either way.

However, as I read through this thread, it seems that the general consensus is that it's ok to tow in overdrive?...Wrong!

I have to ask why do most full size trucks have a tow/overdrive off button when equipped with an automatic?

When you are towing with an automatic tranny in OD there is occasional changes of about 200 RPMs. The torque converter is engaging and disengaging. If it changes very often you want to drop out of overdrive. Taking the tranny out of overdrive will put it in 3rd or ?D? making the torque converter in a constantly engaged mode. What wears out the tranny is in fact the torque converter is being overworked in OD. That is why you don't want to tow in OD unless you are on fairly flat highway and the load is substantially less than the rating of the tow vehicle.

I tow my boat with a Subaru and the owners manual says to keep it in 3rd instead of "D". This keeps the tranny out of overdrive with or without cruise control on. The same applies to my dad's Chevy Malibu. The same also applies to my brother's F250 diesel. Although it has plenty of power, the overdrive is a highway gear for use with minimal resistance.

Look at any manual transmission car. I'd bet dollars to doughnuts that any 5 spd or 4spd with overdrive says to tow a load in 4th gear.
 

itsaboattime

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Re: Using cruise while towing???

OD is intended for long flat streches of highway. Not for towing. I just checked my manual for my 02 f150. OD was implemented to keep the rpms down at higher speeds thus conserving gas. As stated above, if the trans is searching or "hunting" for the proper gear, take it out of OD.

I don't think I have ever used cruise while towing. I am comfortable with my foot controlling how fast my truck and boat are rolling down the road. kinda silly I know, just tap the brake or push a button and the cruise is off. But none the less, no cruise for me while I'm towing
 

lowkee

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Re: Using cruise while towing???

This may add more questions than answers, but don't today's ECU modules learn your driving habits and alter shift points accordingly? Wouldn't non-towing behavior cause the tranny to shift at bad times while towing while on cruise? I'm wondering if the ECU would imagine the weight of the car without the trailer and shift accordingly (not a good thing). Then again, maybe the ECUs arern't as smart as I think they are and they just go by RPMs and grade.
 

Expidia

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Re: Using cruise while towing???

See, I don't know where the OD topic came up. My car does not have an OD selection. It has a sport switch because its a turbo but I don't use that for towing.

My selector just has D so I figured D will automatically switch to OD on the flats over certain speeds. Maybe when towing it knows not to go into OD. I don't know as it's a 2001 and probably the computer was not that smart in those days.

I use 3rd but when I switch to it I forget to shift it back to D and then discover it was not in D 50 miles later.

So it's OK to drive in 3rd all the time while towing, if so that's fine with me because if it uses a little more gas that's OK with me as a trade off for less stress on the tranny.
 

JB

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Re: Using cruise while towing???

What it says in a Subaru or Ford manual about using cruise or OD is completely irrelevant to any vehicle other than the one referred to.

Again: There is no "One size fits all" rule. Read the manual for your vehicle and ignore what other vehicles' manuals say.
 

Jeepster04

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Re: Using cruise while towing???

The issue with using cruise control for towing is that it does not "anticipate" very well. In other words a slight grade generally poses no serious issues but going downhill through a gully and then suddenly up a steeper grade causes the cruise control to apply throttle in ever increasing amounts finally the ECM realizes a downshift is necessary so the whole system sort of overreacts. My technique is to use cruise, provided the tranny does not spend a lot of time hunting (up/down shifting -- or torque converter unlocking/locking). When I approach a hill, I will simply add a bit of throttle (step on the gas a bit) to increase the speed before the hill begins slowing you down. About halfway to the crest you can begin letting off the gas to let cruise regain the preset speed. Unless the hill is really steep the tranny will not unlock the torque converter. The caviat here is everyone drives differently, tows a different load, with a multitude of different vehicles all of which have different towing characteristics. But in the end -- anticipating a hill will generally result in less converter activity and fewer downshifts.

You explained to a T what I do. My cruise also has a cancel button which is about the same as tapping the brake. If I see that the speed is going below what its set at Ill just cancel it and resume once I get over the hill, works great!

For towing, Ive only used cruise when its 100% flat. If there is a hint of a hill coming Ill cancel and take over from there. It tries its best to keep the speed right at what Ive got it set to and when youre towing thats impossible. Ive had it shift down into second at 60mph going up slight inclines which just isnt needed unless its a big hill.

Also, using OD when towing heavy loads will kill the tranny. Just a FYI there.. :)
 
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