This message is for COWPIE1 or anybody else with info regarding a GLIDER TRUCK..=)

I didn't know that you could do that until now. I have a mechanic that works on my truck much cheaper than the dealer. I'm normally only out of service for 24 hours. he fixes it real quick and does good work.

 

A good friend of mine that has owned and drove Petes with Cats and Cummins a long time justb went to work for a company that put him in a freightliner classic xl with the big bunk. Its a 14l Detroit with a 13 and 3.55 rears and every thing he has said about it has been good. He says its stout drives good and gets 6 to 6.5 pulling a van no skirts weight varies alot but he said doesn't affect it much. For this boy to say that it must be impressive. It is bone stock no tune or mods as this company that just isn't their thing.

There isn't a big enough difference in 3.42 and 3.55 to write home about all thou I don't know what HP this truck is set at. I would think its at 515 but haven't seen it. I went from 3.70 to 3.55 in my truck because I had the 3.55 on hand for front and rear when I hulled out my 3.70 rear. I can't tell a difference sitting in the seat except maybe 50 rpms or so I hadn't put the calculator to it.

 

I agree 100%with cetane on the lower gears for starting. Some guys feel that they let the clutch out and the truck goes, so what's the problem?

The thing most people don't realize is that the crankshaft turns your flywheel which your clutch engages which is what moves your truck. The higher you are geared (numerically lower) and the heavier you are loaded and the steeper the hill that you pull out on, the higher the stress and wear is on the ENTIRE drivetrain (not just the clutch), from the crankshaft through the clutch and pilot shaft through the transmission, through the universals and driveshafts, through the rears, and through the axles. And when you pull out in a higher gear, you get more frame flex also, which over and over is really not beneficial, but the additional stress has to go somewhere and eventually cause damage.

The EASIEST on your entire truck is a low, low gear to pull out with. This allows you to just idle and gently, easily, and smoothly go from standing still to motion with minimal stress on everything. The low low reverse allows you to back up and completely take your foot off of the clutch LIKE YOU ARE SUPPOSED TO so that you can crawl into the dock or wherever you are backing.

It's one of those things that most guys won't think they need, but if they understood it and used it, they would never go back to a regular transmission.

The real expense is doing it after the fact.

 

new engine burning a gallon?

 

I thought all Detroits do that? Freightliner told me that's normal

 

I don't think burning a gallon between oil changes on a rebuilt 60 series is unreasonable. I have also heard that a lot of the guys have experienced it stopping after a 100k or so. We will see.

 

Whats funny about a "new" million mile engine is it actually takes 50- 100,000 mi to wear in. The rings take a real long time to grind the liners to get to where they are happy. The loss from all the gear drive and tight bearings actually decrease efficiency by 10% or more. It is backwards, but thats how it works. Most 3406-C-15 that I have seen used liners from lower HP engines still had the cross hatch in them. The rings barely touched the sides in all those strokes.

 

I got my glider from Harrison Truck Center, near Waterloo, IA, a true Freightliner dealer that is on target to exceed Fitz in number of glider builds this year. I figured, why go thru a 3rd party like Fitz, when I can get direct from a Freightliner dealer and have access to the entire build spec system just like buying a brand new production truck? Fitz is good, but I wanted more options.

If one is considering a 3.55 / 3.58 rear end, I would have them take a look at a 3.08. You get the same road speed as a 3.58, just one gear lower. So, with a 13, you would get the same speed in 12th as you would in 13th with 3.58. Why would you do that? Simple. The overdrives are the worse for efficiency. Even the senior engineer for Eaton transmissions stated that at the 2011 MATS. Now, you could totally stay out of the overdrives by using a 2.64 rear (same road speed as the 3.58, just two gears lower), but that would almost require a direct 10, or an 18 if you are doing anything more than straight running. Not a good selection for some, as the 10 direct's are not designed for a lot of torque, and the 18 seems like overkill to some, though I can't figure out why. I got my factory rebuilt 18 for my glider for the same price as a factory rebuilt 13. Price also has to do with demand. 13's are more in demand, so the price reflects that.

But 3.08 gives someone a lot of flexibility. It doesn't sacrifice a lot on start ability (unless you are regularly crawling out of gravel pits or loading grain on soft cropland), you can run in the first overdrive, which is more efficient than running in the second over on a 13 or 18. And, if the need called for it, and you needed to "put a wiggle in it" and get on down the road, you have the top hole you could move into and run at Texas type of speeds without rapping out the engine. On a difficult pull and you need to drop a gear, you would be dropping right in to direct drive (11 on a 13, 16 on a 18 ), where the maximum efficiency is, and pull like there is no tomorrow.

I regularly pull loads that hit the 45K mark. Even do some occasionally that my carrier's company trucks can't scale, since I can legally scale up to 48K in the box, with full fuel tanks (I have 100 gallon tanks). And I do it with an 18 using 2.64 rears on a fair amount of back woods, two lane, hilly roads. I can pull right along with everyone else with the same weights. And that is with me using a 500 Detroit 12.7 pre-egr. Granted, I do take a little bit of a hit on start off, and I don't "get out of the hole" as soon as some others, but I am not trying to drag race either. And getting averages in the mid to high 7's, even pulling the heavy stuff and running the back roads, is not bad. Granted I get some 6 mpg's here and there in the winter, but I also get some serious 8 mpg plus at times. All balances out to around mid to high 7 mpg year round.

Now, that is not the ideal setup for many, and I understand that. Going with 3.55 is not a terrible idea either. But there is a lot to be said for splitting the middle and taking a close look at 3.08. You could do that nicely with a 13 or 18, your choice. The 18 has a lot lower bottom than a 13, and that is the only solid edge it has. With something like 3.08, you wouldn't need that low of "grunt" or the need to split the bottom, like with 2.64, so the 13 would be a good choice. And you still have flexibility at the top for the faster speeds that all the states are ramping up to, without racing the engine.

The 12.7 can really be made to work well. And I can keep up, or even walk away from most of the newer engine trucks pulling the same loads. And my factory rebuilt 12.7 using oil? How about maybe a quart in 15,000 miles on mine. I have 210,000 miles on this engine, and have never had to add a gallon of makeup oil between oil changes.

If going with a glider, consider the new Detroit steer axle. I did it on my glider. I still have the original steer tires (Michelin XZA3+) and they still have between 8/32 and 10/32 left on them. No cupping, no river wear. I spec'd Conmet Preset Plus hubs on the steer axle and put on Balance Masters. For the rear, I got Meritor 14x axles with full lockers and running wide based Michelin XDN2 rubber. I know, I know, they are not as efficient as Xone XDA Energy's, but they still have a respectable low rolling resistance of 105, and they really have made a difference in some nasty stuff I have had to go thru in my area, especially with the lockers thrown in, which has been a need a few times. See, I don't just pull on the 4 lanes. I actually have to go down some pretty muddy gravel roads occasionally. And staying up north all year, I get to cut some trails in snow frequently.

Overall, I did my glider right. The only thing I could have considered different and been comfortable with, was using 3.08 instead of 2.64. I am not regretful of using 2.64, but I would have considered 3.08. 3.55 as a last resort.

I tweaked a lot of stuff on the final put together before this one started pulling freight. Overall, this glider has been the best truck I have ever driven in over 3 decades at this game. I ordered the Arctic insulation package, and the premium noise abatement package on my glider. This winter, even when hitting -20F actual, I have yet to turn on the water to the sleeper!! The cab heat alone does an excellent job of keeping things warm. Hard to believe with a Freightliner, but it is what it is. I did have an Espar heater installed at the factory on the glider build. If you spec a truck right, and keep away from typical company truck specs, you can really come up with something special.

 

I read an Eaton service bulletin last week that said they did not recommend running in 12th with a 13 or 16th with an 18 for extended periods that it causes heat build up. I don't see a problem as long as the gauge reads ok. I mainly just wanted to ask if you had noticed any heat rise in that gear or if you run it much. I plan on reading it again to make sure there isn't something to really look for jus hadn't gotten around to it yet.

 

I'm going to say, Why not buy used. ? Da , da.