Death Valley in Summer - NOT GOOD! 6-speed troubles...

[truckmen]

Okay, so, I know better but did it anyway.

I'd decided to run across Death valley with this load of cars. So after pulling some of these steeper grades grossing 34,000 lbs (at least), I dropped into a low as first gear and topping out at these hills at 5 MPH, saw coolant temps reaching 237 degrees and oil temps hitting 252 degrees. Needless to say I let the truck run down the hill very easily to try and get as much of the 115 degree ambient temperature through the radiator as possible to get the numbers down before something blew. Nothing did and I did not lose a drop of coolant; a testament to the integrity of the system

Once back "in civilization", driving across NV, AZ and NM, I'd noticed a few things different and wonder if it is related to high temps. During downhill runs and in 6th gear, with the engine brake on, my transmission will jump out of gear. It happens only once in a while when I am at certain speeds and engine RPMs and usually only with the engine brake on.

Question:
Could I have damaged a synchro gear?
If so, how difficult is it to drop the transmission and replace it?

Yes, it's a 6-speed manual G56 hooked to the 6.7


Half way up at Towne Pass on Hwy 190 and before dropping down to Emigrant Campground

 

[NIsaacs]

Nice load! When they jump out of gear it is time for bearings, minimum. Since it is 6th with the issue, the pocket bearing will be the worst one. Is your truck a 4x2 or 4x4, that will determine the level of difficulty to r&r. They only get worse, so the sooner you repair the better.

Nick

 

[truckmen]

Nice load! When they jump out of gear it is time for bearings, minimum. Since it is 6th with the issue, the pocket bearing will be the worst one. Is your truck a 4x2 or 4x4, that will determine the level of difficulty to r&r. They only get worse, so the sooner you repair the better.

Nick

It's a 4x2. Bearings? Okay, I've got 164,000 miles on the truck right, now mostly with loads like this one.

 

[schmeg]

Hauling 25K plus with a G56 truck. Impressive.

 

[cerberusiam]

Okay, I've got 164,000 miles on the truck right, now mostly with loads like this one.

And that would be the reason it likely need bearings at that mileage, 30% over rated maximum which it was borderline with anyway.

 

[truckmen]

Hauling 25K plus with a G56 truck. Impressive.

Thanks, I am usually at 34,000 lbs gross and I try as much as possible to baby the truck.
What could be my alternative to the G56? Is there something out there that I could add for my gears?
I sure could use another gear. My rear axle is 3.73s

I looked at Gearvenders at:
http://www.gearvendors.com/product/manual-6-speed-g56-2/?TYPE=COMMERCIAL-BUSINESS&FUEL_TYPE=DIESEL
but that is currently not in my budget.

 

[cerberusiam]

What could be my alternative to the G56?

A bigger truck with components rated for the load is the only good answer. Unless you want to back that load down to something reasonable you WILL have the same problem again. The G56 is simply not rated to handle that kind of weight unless you regear to some deep gears, all the leverage is in the trans and it is too much for it. A truck rated at those weights is running 4.88's or 5.12's and a true MD transmission, you cannot baby that trans enough to compensate.

 

[NIsaacs]

The Gear Venders is an overdrive so that really won't help. You need an underdrive. Plus it is not heavy enough for the Cummins torque and the exhaust brake can only be used in direct.

Since you have a 4x2 the cost to re-gear the rear axle might be an option. I wouldn't go any lower than a 4.10 or you will lose empty cruising. There can be a down side to that tho, as it allows a longer and harder pull in 6th, the weakest gear in a 6spd manual.

Nick

 

[truckmen]

Okay, these last two posts are points well taken, and it looks like I have been on borrowed time all along.
Yes, I think you both are 100% correct and it's time I make the necessary adjustments.

I never had planned to haul cars with this truck when I'd purchased it. it was only to pull my 5th wheel camper which itself is nothing small weighing in at 18,000 lbs but it is sure heck of a lot lighter than this ridiculous weight I've been dragging over the Rockies and across the country. The wally-Mo 4-car trailer alone is 10,000 lbs empty. Then to load 4 cars/trucks on it does put me over the top (so to speak).

Kind of a bummer to accept this but it's pretty plain to see. You gotta hand it to me though. I've got 164,000 on it and almost all is with heavy weight. This Ram 3500 has been a fantastic machine. It kept us fed and most of the bills paid but I DO see the handwriting on the wall.

I'm not able to shut down just yet as I have no alternative so, let see how long I go before I'm down with a catastrophic failure. Anyone wanna take bets on how long I'll last?

 

[promisedland]

I will not take a bet
But it would be sweet to pop a MD truck trans in there with 10~ gears or so, I think that would be cool.

Thanks for posting, interesting to see what folks do with their Rams.

 

[NIsaacs]

I will not take a bet
But it would be sweet to pop a MD truck trans in there with 10~ gears or so, I think that would be cool.

Thanks for posting, interesting to see what folks do with their Rams.

X2 and I can understand the need to keep some income rolling in, maybe something will pop up sooner rather than later. In the mean time, stay out of 6th as much as you can. Keep us posted, there is nothing wrong with hard work and we can't always pick the right equipment at the time or the most perfect job.

Nick

 

[schmeg]

A 4.10 geared Aisin gets you 30K+ on towing. Of course that means getting a new truck.

 

[transe]

A 4.10 geared Aisin gets you 30K+ on towing. Of course that means getting a new truck.

Yes, info I have says a 3500 with Cummins 6.7, Aisin trans, and 4.10 axle is good for 39,100 lbs GCVW. Even a 3.73 axle will handle 33,800 lbs.

 

[NIsaacs]

A 4.10 geared Aisin gets you 30K+ on towing. Of course that means getting a new truck.

Yes, I wonder how they pulled that off, when the 5500 is rated less, even with 4.88 gears. I am afraid I would ignore Ram and get the 5500 anyway, if I were towing trailers in the 30k range.

Nick

 

[Newsa]

Just curious if you upgraded the clutch?

And what transmission lube are you using in the G56?

 

[cerberusiam]

A Ram 5500 would give you some breathing room there as they are close to 40k combined weight, even the 4500 would be much better. couple that withe AISIN transmission and you have a much better gear selection than the G56.

There are some changes you could make to your existing truck but they are going to be rather expensive. Since you likely need a transmission finding the late model AE version would help with the OD gear and allow you to regear to 4.10's. A set of 20" rims with the correct size tire will compensate somewhat for efficiency, a 33-34" tire and a .74 OD gear with 4.10's would be much better than what you have now. A 4.30 gears would be even better but limit the top end somewhat but speed is probably not what you are looking for. An OD cruising rpm of 2100-2200 rpms at 70-72 mph is what I would shoot for with gears, tires, and OD ratio.

The stiffening cradle for the G56 would probably help you a lot with heavier weights. The single biggest problem with the G56 is the case flex under stress, high loads want to spread the counter and main shaft causing most of the failures. Not much can be done about the gear contact in 6th other than regear and run the best fluid available, definitely not ATF, and get a cooler system on the trans. Second point of failure on the G56 is the amount of heat under load it can generate, that will severely reduce life expectancy no matter what other changes are made.

If you cared to spend the $$ and coordinated it correctly you could do the gear swap, trans swap, and tire\wheel swap all in a day or 2. Adding the cooling system might take a little more but not a lot of time. As a guess, that is probably $10k worth of changes and that becomes the sticking point, is that platform worth it. If the truck doesn't own you it is a viable option, then all you have to worry about is getting the mass slowed and stopped effectively.

 

[promisedland]

My I ask why you where @ 5mph coming up some of those hills? Your rpms where probably quite low @ that speed...

 

[truckmen]

A 4.10 geared Aisin gets you 30K+ on towing. Of course that means getting a new truck.

4.10 gears would have me a lot slower on the "super slab". With my 3.73s, I am doing 72 at 2200 RPM, if memory serves me.

 

[truckmen]

My I ask why you where @ 5mph coming up some of those hills? Your rpms where probably quite low @ that speed...

Coming out of Stovepipe Wells up Rt. 190 towards Beatty, NV eastbound, at one point, I dropped down to low gear (1st) and it sure did not like that. I just could not even stay in 2nd for a few hundred feet.

 

[schmeg]

There are some good points made on upgrades. Downfall is they all cost money on a truck with a few miles on it and 640 pounds of torque without tune. When you add it all up would it be more cost effective to trade up to a 3500, 4500, or 5500 with an Aisin and 4.10's? This truck is your lively hood. Having a dependable truck is my first priority. Having pulling capability is also a main priority for me. I'm only pulling 19K but I don't want the truck feeling like it's going to come unbuttoned when pulling long grades. I would get the right tool for the job if you can swing it. You'll be happier and it will give you years of revenue.