First time towing with Cummins & w/Manual transmission

[Fader]

Hello all. I had my first opportunity to tow with a Cummins pickup this last weekend.

It also was the first time I pulled anything utilizing a pickup with a manual transmission.

At the ripe young age of 37 I pulled the trigger & bought a 82 c30 Chevy with the 6bt/nv4500 this past fall & finally learned how to drive a standard transmission.

Anyways... that truck is parked for the winter but I also bought a 97 Ram 2500 Ram seven weeks ago with the same setup plus 4 wheel drive.

It was definitely interesting being in control of the gears towing... I really enjoyed it except for the one stretch in town during relatively heavy traffic. That portion felt like a lot of work going stop light to stop light.

I didn't really take a lot of time researching it before going for it but I knew a few basics....I would love any advice/tips before I tow again.

I was pulling a Ditch Witch RT45 trencher (5500 lbs) & a 24' trailer that clocked in at almost 3000 lbs... I love good trailer brakes!

I believe the truck to be in stock form or very close performance wise. (For now)

I have previously towed with an old 6.2 diesel pickup as well as a 3/4 ton chevy w/ a built 454 & a late 90s chevy with Vortec 454... this was a much more enjoyable tugging affair.
In all fairness the big blocks were pulling more weight most of the time but I've never been able maintain speed going up hill.

I utilized first gear on most stops which I never do around town normally.

I didn't use 5th gear when towing... (seems like I read that somewhere)

It felt comfortable going 60mph +/- which was all that I was after anyways...you gotta stop at some point.

RPMs never got above 2400 in 4th gear & that was laying into it some going uphill. (354/355s I gotta look that up now)

I'd like some aftermarket guages...obviously boost & egt.
I'm thinking maybe transmission temp, oil, temp, & maybe fuel pressure??
I know that a few of those are redundant with the factory gauges but they are 22 years/230k miles old.

Being a regular cab 2500 I don't think that this will ever be my big hoss super pull truck that I daydream of. The big dually Crew Cab Chevy with a Cummins may be a better choice with a longer/wider base.

Additionally what would be some good mods to make?
Air filter or leave the stock setup?
I saw that Geno's has a deal that bolts onto the nv4500 for added capacity & cooling effect.
I am definitely going to make sure everything is in great mechanical shape & I have guages before I even go down the road of turning the fuel up any.


Sorry for the long post... just wanted to share & get some good towing tips to make every futire trip successful.

 

[GAmes]

The coolers can do no harm, they add a couple quarts of oil so heat is dissipated faster. Save the transmission temp gauge money. They are essential for towing with an automatic but I found they are worthless with the NV4500. A fuel pressure gauge is essential for troubleshooting if you have any fuel delivery issues. In addition you can use it to decide when to change filters. Not throwing away good filters will pay for the gauge in a few years. I went through a lot of NV4500s before upgrading to the G56. For a time I had a temp gauge and it never gave me any indication of transmission failure. To make the release bearing last longer shift to neutral and let the clutch out while stopped. You might consider an exhaust brake if you tow often, especially if in the mountains.

 

[KATOOM]

A '97 means you have the 12 valve so there isnt much you'll need for gauges besides boost and pyrometer. I have a 5 speed with Fastcoolers and a transmission temperature gauge monitoring in the cab. I like my setup...but I also tow my stupid big 5th wheel trailer in the triple digit summer heat and wanted all the assurance that things werent cooking. That said, as long as you stay out of 5th gear while towing anything over a couple thousand pounds, you'll be fine and shouldn't worry.

As GAmes said, an exhaust brake is essential. The problem you'll face is needing to upgrade to 60 lb springs for the exhaust brake to work.

 

[Seabee]

I have a 97 12 valver too. I run the dual coolers on mine. I am not a member of the zero tow in 5th gear. I do use 5th, but I don't allow it to go below 1750 RPM on a hill. I shift to 4th at 1750 RPM before it starts lugging (1500 RPM and lower). I normally don't tow over 8000 lbs. All that said, I did break some 5th gear teeth at about 125K miles BEFORE I learned not to lug it in 5th. I would let it drop way down if I could top the grade without downshifting. Not smart to be lazy. My theory (and others) is that the diesel has so much more crankshaft torsional hammering effect on a set of gears in a lugging scenario, that it initiates micro cracking of the gears. Of course over time, those micro cracks get big! When it failed I thought there was a pile driver near by before I figure out what was going on! By keeping the engine at higher RPMs in 5th, I avoid the "hammering" that occurs when lugging a diesel. I only have 15K on the new transmission, so my theory hasn't been proven yet. I have been working on diesels and heavy equipment for 44 years, so I hope my opinion has some merit based on experience. As always, use free advice at your own peril!! As a mechanic, It just wears on me to hear an engine running at a higher RPM than it has to, or should for extended periods of time.
Show us some pix of that Chevy conversion. I love those swap out builds..........

 

[KATOOM]

Seabee, based on all the research information I've found over the years regarding the 4500 and all its downfalls, I would say your 5th gear problem was not related to crankshaft hammering but more related to heat. If you tow the kind of weight you do in 5th gear then I can assure you that the temperatures generated in that transmission were HOT. And while towing in 5th gear means all that heat comes from one source...the 5th gear. Which also means that the 5th gear itself is running much hotter than the fluid and its surroundings due to dissipation. Its likely that the heat affected the metallurgy and eventually caused breakage due to the strain the Cummins can place on the drivetrain.

For example, when I'm pulling a 14k pound 5th wheel in the triple digit summer in 4th gear (1:1 direct) the transmission temp will remain in the 160*(ish) range on flatland. Pulling long hills, if I can remain in 4th gear, the transmission will get no hotter than around 175*(ish).
But if I ever have to downshift into 3rd then the temperatures will climb. Hold that gear long enough on a long enough hill in hot enough weather and I'll see transmission temps upwards of 190*-200*.

Now that said, just cruising down the highway at 65-70 mph unloaded not pulling anything in 5th gear, the transmission temperature will climb to around 175* and stay there. In the winter it may only get to around 150*. Granted it takes at least 30-45 minutes to reach those temperatures but just pointing out that driving in any gear ratio besides 1:1 will generate a lot of heat.

The story behind the guy who invented Fastcoolers was that he was a hotshot driver who kept dealing with 4500 problems. Found out it was heat related as 275* was normal towing temperatures in 5th gear. After he made the coolers he was able to bring that down to 225*. Still too hot in my book for constant use but nonetheless, it proves a point.

 

[MLee]

I see your concerned about trans temps and when to use the 5th gear, weather or not while towing. We all have our own theory on how to do it, and I'm not going to tell you how you should drive your truck we just have to be knowledgeable about these trucks, but I use 5th when towing and on the interstate on flat highway, and 4th on hilly terrain I just don't lug it ,and use 4th from 55-50 and below.
Also noticed no one made mention of the KDP on your 97. This year is very prone to drop this guide pin and cause a head ache for the owner, check yours or get some info on it from whom you purchased it from to see if it has been done. If not fix it asap. Sounds like the conversion is a good setup, you just have to learn how to drive this 5 speed trans. I had a problem when I bought mine and learned fast--Don't lug it, shift it before you get to this point.
Good luck in your venture.

 

[Seabee]

I certainly won't discount your position KATOOM! (I love that name; as I ride a KTM EXC 400) I have read your theory espoused before.
I would expect bearing failure before metallurgical failure from heat. I'm not sure at what temp our synthetic gear oil breaks down. Most synthetic engine oils are rated well over 300 degrees F. Dino engine oil should never exceed 275 degrees F.

 

[KATOOM]

All oils start to oxidize above 180*. The rate only increases from that point on.
And synthetic fights oxidation better than conventional merely because of its molecular uniformity...and whatever the proprietary additives it has may offer as well.
But that said, here's a printout of SyntorqLT for your records. Its actually really good stuff, but running constant temps close to 300* is going to turn any lubricant into worthless goo with a very short service life.

Oh and thanks for the compliment too...

 

[mpsmdsr]

Hi KATOOM! New to this forum. Intent was to inquire what oil to replace my old NV 4500 oil with, because I read somewhere that GL-4 additives a hard on that synchromesh. Any comment? Obviously you are very satisfied with the SyntorqLT. Thanks, MPSMDSR

 

[KATOOM]

Hi KATOOM! New to this forum. Intent was to inquire what oil to replace my old NV 4500 oil with, because I read somewhere that GL-4 additives a hard on that synchromesh. Any comment? Obviously you are very satisfied with the SyntorqLT. Thanks, MPSMDSR

Welcome...
I've never heard that GL-4 is hard on synchromesh. Actually GL-4 is needed because of the soft yellow metals. Its said that GL-5 will cause failure of those components and separation of the composite coating on the 4500's synchros so whatever you use, make sure its GL-4 specs.

As for other fluids/types/brands, there is a plethora of threads out there on the internet where people talk about the alternative fluid they're using in their 4500. Most claim no issues too but what you're looking for is the honest people who've hopefully updated their posts/threads revealing any issues they had over time. At that point you then have to understand if there's enough information collected to know whether the failure was related to the fluid, driver influenced, or simply random component failure.

 

[SAndreasen]

Like buford t justice says . “You can think about it but don’t do it” and thats run anything in an nv4500 but an oil that specifically says gl-4 and it should says meets chrysler part number for nv4500 transmission or you’ll have problems trust me.

 

[SAndreasen]

https://torqueking.com/product/9002...l-transmission-oil-by-red-line-50504-1-quart/

 

[BigPapa]

I’d stay away from wherever you read GL-4 shouldn’t be used in the NV4500.

What lube to run in the NV4500 comes up every couple months. There are LOTS of threads on it. This one probably has the most info on it.

https://www.turbodieselregister.com...e-75w140-or-75w140ns-and-nv4500-fluid.266470/

 

[NIsaacs]

but don’t do it” and thats run anything in an nv4500, but an oil that specifically says gl-4 and it should says meets chrysler part number for nv4500 transmission or you’ll have problems trust me.

He said don't use anything, but GL-4. The Buford T Justice throwed a monkey wrench in his statement

 

[SAndreasen]

He said don't use anything, but GL-4. The Buford T Justice throwed a monkey wrench in his statement

You can’t use gl-5

 

[khalsey]

I have a 1996 3500 with the NV4500 with 3:54 axle that I purchased new that now has 104,000 miles. Almost all of those miles was towing a 5th wheel trailer. The last 2 5th wheels were/are in the heavy category. My Landmark loaded for our full time RVing is just under 16,000# and I tow in 5th all the time as long as the boost is under 16# and RPM is over 1800 and I have been towing it for 14 years. Other then updating the 5th gear nut before it came loose and adding cooler on 1 side and a filter on other side the trans hasn't been worked on and still on original clutch. I have changed the lube about 3 times. I hope/pray my luck keeps holding out. My wife and I are meandering our way to Florida now with her driving the car and me driving the truck.