Whats the rule for towing in 5th gear?

[RSchwarzli]

Is there a rule for towing in 5th gear? Like for example, no problem as long as you are above 1800 rpm and you dont lug it...



Or is it just plain no stupid. Run 4th and rev it out.



Trailer is 26' Haulmark at about 8K lbs. Not much.



Thanks!



Robert

 

[Greenleaf]

There is a fellow just short of a mile from me who tows his big fifth wheel in top cog and has wrecked three manual transmissions. He likes to lug that old 12 valve and is rewarded with a hearty tow bill and down-time.

 

[RSchwarzli]

I see. So you think it is OK then if I dont lug it?

 

[Rams-n-Hogs]

In my 96, if I can keep the rpms up around 2000 in 5th, I'll run it there. Usually on the interstate doing 60, or better. If I'm on a 2 lane road, or in the mountains, I'll usually leave it in 4th. I usually run about 2200 rpm, which is between 55-60 in my truck. As long as you don't lug the engine, you should be good.

 

[HBarlow]

Tow haul mode and fifth gear is intended for towing in my C&C w/Aisin. When I select Tow/Haul mode it omits sixth/2nd OD and uses fifth as top gear. I haven't been around the MOPAR six speed automatic enough to know but assume it is similar.

My truck runs well into the torque band in fifth and if speed drops it will downshift to 4th/direct. I rarely need or use 4th.

Our Cummins engines produce maximum torque from 1500 or 1600 rpm (depending on programming) to about 2700 rpm. You will never hurt one running it at 1800 or down to 1600.

 

[JLEONARD]

You will never hurt one running it at 1800 or down to 1600.

No you will never hurt the engine, however the question is regarding the manual trans.

No you do not want to lug it. Keep the rpm up as suggested in most of the posts.

Fuel wise it won't make much difference so why chance the trans.

 

[RSchwarzli]

Hey Harvey. Sorry to throw you for a loop. This be the first gen forum. I am thinking G 360 Gutbag.



So really, the answer is no. Was more thinking for engine noise and operating outside of its powerband. As I tow at 75 MPH... .



Granted, I guess I should not complain. I have 3. 07s with the 5 speed. You poor 4. 10 guys!

 

[cerberusiam]

I see. So you think it is OK then if I dont lug it?

Don't lug it at all, bad idea. Keep it out of the harmonics zone all the time or it will suffer.



Don't full power on and off in 5th either, that will destroy it just as fast. Roll into the throttle to accelerate and when you come off the throttle roll if off as slow as possible to minimize any TQ lash.



You can usually push the acceleration up to 4th but when you go to 5th take your time and minimize the stress, it will like you a lot longer.

 

[Alexdring]

I wouldnt lug it at all. Like said above 1800 to 2000 rpm's is ideal. I know this is a first gen post, but when I lug my 02 I notice my EGTs skyrocket. I simply shift down to fifth and they drop and better power. The only time I use top gear (6th) is flat highway. Any hills or corners I just keep it in 5th.

 

[ZedMikey]

... I simply shift down to fifth...

Suuure, rub it in.

 

[Alexdring]

Sorry, but it sure is nice having that 6th gear. After 7 years of towing with my 91 and its 3 spd 727 auto, I am a kid in a candy store. :-laf

 

[RSchwarzli]

Don't lug it at all, bad idea. Keep it out of the harmonics zone all the time or it will suffer.



Don't full power on and off in 5th either, that will destroy it just as fast. Roll into the throttle to accelerate and when you come off the throttle roll if off as slow as possible to minimize any TQ lash.



You can usually push the acceleration up to 4th but when you go to 5th take your time and minimize the stress, it will like you a lot longer.

Well that is good to know! I up until this point have liked passing cars on 2 lanes in 5th! Good pickup with the 740 ft/lbs!



SO I guess drag racing in 5th is no a no no too! :-laf

 

[HBarlow]

Ooops. Sorry, I was off the track. I saw your post in the "new posts" list and simply looked at the truck in your signature and assumed (wrongly) that you were talking about a six speed automatic.

I towed all the time in sixth gear with my '01 NV-5600 and it lasted 302,000 miles but from what I have heard and learned about the five speed manual it is probably a very bad idea.

 

[NIsaacs]

The little bugger is tough. Like others have said, don't abuse it but don't be afraid to use it either. On a tough hill with a load use 4th.



Nick

 

[JLEONARD]

SO I guess drag racing in 5th is no a no no too

Yes absolutely no drag racing in 5th while towing a trailer.

 

[RSchwarzli]

No drag racing WHILE towing! Drag racing happens when empty! LOL

 

[Alexdring]

Just a hunch but I think your ET's might suffer a bit drag racing with a trailer. Plus how would you stick on your wheelie bars with a trailer hooked up.

 

[pepecat]

at or near stock power levels you could tow in 5th gear citing what was said before "don't lug, etc". I would not venture a guess to say what was deemed 'safe' or otherwise for the getrag with towing twins, big sticks, big intercooler etc.



And correct me if I am wrong but I recall that the "360" in Getrag G360 specifies 360 ft/lb as max constant load rating of input torque does it not?

 

[RSchwarzli]

If so, that would explain why they failer. The trucks had 400 ft/lb min stock!

 

[pepecat]

That is correct. . I know that this envelope was pushed for sure with this transmission. I know that the 400 ft/lb wasn't throughout the whole range of RPM stock but the cummins seems to have a long flat torque curve from the dyno sheets I've seen.