fiver auto towing question

[LMautone]

Picked up our new Coachmen Chaparral fiver. 1. Trucks pulls it fine. I keep OD off. My rpm's are noticably higher. Is it ok to maintain rpm's of 2200-2300 at 60+ mph for extended highway driving? Truck sounds great but thats alot higher than my usual 1700 rpm's. Also, I had axles on the fiver flipped and trailer is still a tad nose high when towing. Do you foresee any longterm problems? It towed great, stopped even better with my Prodigy set at 6. 0. And does backing the fiver up, Took 20 minutes my first time in my tricky driveway, hurt the trans? I heard the auto trans heats up real quick in reverse. thanks for the help

 

[Mundgyver]

You might want to consider putting on a secondary transmission cooler with what the truck has already if you are going to be towing allot. The cooler you can keep the transmission fluid the better off you will be in the long run in the way of repair bills or problems that it will prevent. Have fun

 

[D White]

These engines love those kind of rpm's, wont hurt it a bit. Actually thats the sweet spot with my truck, I even run it 2500 to 2700 quite often. Keeps the line pressure up running the higher rpm's. I try not to let them get below 2000, especially when towing. Once you get used to the sound of the higher rpm's, anything under 2000 won't sound right.



There's tons of people out there towing with flipped axles. You shouldn't have any problems as long as your not real nose high. Keep track of your trailer tires and watch them for unusual wear. If your not getting any fishtailing, your probably ok. I used to have the same problem with mine being nose high and would load the truck bed and front part to the 5'ver with most of our stuff that we take along, helped a lot. Made the pin weight a little heavier and it would ride a little more level.



Might want to consider a transmission temp gauge, that's the only sure way of knowing where your temps are at. I've never noticed any high temps while backing but also have a double deep pan which really dropped my temps down, about 20 degrees cooler on average.



Hope this helps,

DW

 

[barryg41]

I made a trip up to Wyoming last summer. I put the cruise on 68 (out of OD) which is 2750 rpm's. The Cummins had fun pulling like that for three weeks. I had an average of 10. 5 mpg. The trans temp never got above 135. It did go to 175 when crossing Raton Pass. OAT was 85.



Last month I made a trip to Dega and this was the first pull with an EZ. I put the cruise on 71 (in OD) which is 2k rpm's. It held the hills with plenty of go peddle left. I got 12. 5 mpg on that trip. On this trip the trans temp never got above 105. OAT was 80.



The Edge EZ makes a big difference!!!



What I have found when parking my camper is that when I have to stab it more than four times the trans temp will go over 200 degrees quickly. If it only takes a couple of times, it's usually not a problem.



Take care...

 

[LSMITH]

20 minutes backing the trailer is a great recipe for dangerously high transmission temperatures. You should put in a transmission temperature guage so you know when to put it in nuetral and rev it until the temps come down. High temps is the easiest way to kill an auto transmission that I know of.



Pulling at higher RPM is not hard on anything but your fuel bill. The 24V wants to pull at 2000+ RPM anyway, and towing for days at 3000RPM is not going to hurt a thing. Hope this helps.

 

[billr]

Some fifth wheel pins are adjustable. The one on my fiver is. If the trailer is not too old it may work for you.

 

[dodger22]

barryg41 - what setting did you use for your EZ? Before I had gauges installed I ran mine on the lowest setting and was pulling a 10,000lb 5'er without any ill effect.



I would like to pull with the higher setting once I establish a base line with the current set-up.



Richard

 

[LSMITH]

Dodger, you are not going to see any difference what-so-ever in max EGT with the settings on the EZ. The jumper does not control maximum fueling, only at what boost level fueling starts. Smoke control and fuel economy are the only reasons the jumpers are there. Hope this helps.



PS, if twoing make sure you have the elbow in or a turnbuckle on. EGT can get high with an EZ and no boost mods.

 

[barryg41]

Dodger... just for the record. It is set on three. That is the setting from the factory. I also use the boost elbow. The only time I see smoke is when I stomp it from a stand still. Just a little puff of smoke. I dont do that too often since I am into towing and not hot rodding.



I have my SPA's set to alarm at 1275 and I cant hit it loaded or not.



LSMITH is right obout the fueling thing. The EZ starts fueling at 2 lbs. and stock it starts around 4 lbs. I cant tell you what happens at the top end, but someone might be able to say one way or the other.



Take care...

 

[dodger22]

Thanks for setting me straight on this. When I had the EZ installed I was told to keep it on the lowest setting with towing (also I had no gauges at the time). I was also under the impression that the EZ advances the timing, is this correct?



Thanks LSMITH re comment about turnbuckle. I'll do a search on that topic and get that done too.



Later,



Richard

 

[Jim Fulmer]

barryg41

Instead of you test driving my truck empty it would be cool to tie it on a trailer and go drag it around, I would like to do this too!



Dwhite, not rain on your parade but RPM's doesn't affect line pressure that much, what you are refering to is pump speed. With a guage connected I can go for a pressure test drive and lockup pressure doesn't gain much from 2k to WOT, but we know pump speed does. When on the dyno, I do it in O/D Locked, just get the R's to 1800-2000 and let her rip



Jim

 

[barryg41]

Jim, you are so right! I would have loved to hook up my camper with your truck and seen the difference in our transmissions. Your extra HP would also have made a difference.



You also said that the R's dont make that much difference when running around 2k to WOT for transmission line pressure. When I leave from a red light, I get R's up to 2k and keep it there till lockup. (out of OD) Then when I get above 65 I put it in OD. But what if I launch say at 1500 rpm. Is the transmission line pressure lower at that rpm or is it the same at 2k? I have a shudder when shifting at a lighter throttle, but at 2k the shudder is gone. I also noticed that the transmission temp stays lower when easin up to 2k and getting it to lockup sooner than later. Which of course means no slippage.



What I need to find out is, at what RPM do you achive maximum transmission line pressure. Then I could launch at that RPM and not waste fuel when I dont need to. I am not in a hurry to get to 70, I just want to get there with the least amount of fluid drive time with maximum line pressure and into lockup.



Maybe I am asking for too much... .



Take care...

 

[rfielding]

So what truly is the best way to tow... I have been given so many different opinions... .



On highway, is it alright to tow in OD... . in the past i have done both... on and off... seems like the RPM's are way up witht he OD off...



When on hills, local roads, etc i have always towed with the OD off...



2500 2 wheel drive extended cab... carrying Lance Camper and towing 21 foot boat...



Thanks.

 

[D White]

Fulmer, You've apparently done a pressure test thru the rpm range, I'm curious to know what rpm max line pressure was achieved. Seems like that would be some info that would help everyone.



You have a DTT VB, not sure if max pressures will still be achieved at the same rpm.



DW

 

[Boldt's Wagon]

Rfielding: Tow in OD if you are over 1800 rpm in OD and below 15 psi boost, other wise use 3rd or slow down.

 

[rfielding]

Thanks for the advice...

 

[jbone]

Need to get those gauges in there w/EZ---I got 4. 10 and it tows about 2k (65) in O/D just fine---think those rpm are reason most serious towers have 4. 10... ... ... ... ... my 2 cents worth... . R, J. B.

 

[RustyJC]

Originally posted by LMautone

I keep OD off. My rpm's are noticably higher. Is it ok to maintain rpm's of 2200-2300 at 60+ mph for extended highway driving?

I certainly hope so since 60 MPH in 6th is 2000 RPM and 70 MPH in 6th is 2350 RPM with our 4. 10's. We pull a 13,500 lb 5ver, and this RPM range puts us right in the Cummins' sweet spot for towing this weight.



Rusty

 

[LMautone]

Thanks for the replys. I feel more comfortable now.

 

[Goddard]

anybody pulling a trailer of any kind and has 4x4 ... . imo... . should get one of bobv's 2-low kits. this would make things easier on your trans for backing or tight places. put one on my truck couple weeks ago and love it. works great. bobs kit has everything you need and quality parts!