Flow Below Added

For running those speeds, 75 at times that's still really good. This past Qtr just running the one truck I'm at 6.34 on all miles. And that's running 65-68 in an old truck....... sometimes 72-75 when I'm in a hurry in the morning Lol.

 

My left knee doesn't know what to do with itself.

I didn't have any issues this past winter. That said, it was a real mild one and as luck would have it, excellent timing not to be out when the two ice storms went thru the midwest. I white knuckled it a little in IL on I-74 when some freezing mist set in, I can't say it would have felt better with a manual transmission. The old tried and true "slow the f down" method worked ok.

The first Mack I bought off the lot had it. After a trip I decided it wasn't such a big deal, so spec'd the second one with it. I don't even hear it any more. I figured sooner or later it may play a factor with insurance at least, so just sucked it up and ordered it.

In fact, the '22 I'm in reads speed limit signs for me and gives a warning if I'm 5 or more over. I heard somewhere if you trip that warning about 15-20 times in a row, it sets an error and shuts up until you restart the truck. Of course I'd never do such a dangerous thing to prove that. Nope.

I think that's an Eaton feature. I rented a T-700 with a 12 speed auto and that about drove me nuts too so I used manual mode to mostly get past it.

I happen to be based near Atlanta so do stop-n-go now and then. My Macks tend to make better gear choices than anything else I've rented. Even that isn't fool proof. I found the secret to smooth Volvo/Mack slow ops is turn the jakes off and use as little throttle input as you can get away with. Keep rpm below 1200 and it will not upshift. With jakes even on low, the transmission will have hysterics. I just use the foot brake to maintain distance and that doesn't happen.

 

The DT12 is light years ahead of the old eaton transmissions, even if you limit comparison to how much abuse it can take before it 'over heats'. The 'modern' eatons are better, but I'd still prefer a clutch or a DT12 in those "you want it WHERE?!?!?" situations.

In regards to your other question, I've been a pumpkin driver for the entirety of my 12 year driving career, mostly due to where I chose to live. Other otr gigs don't offer any advantages and local pays significantly less than otr.

You also can't drive old iron the same way as the new crud. It's one of the reasons the big fleets switched to autos. The 'old skool' drivers kept driving DD15 engines like they were DD60s even though the shift points were radically different. I can't speak to a 99 engine, but in 2010 (my first year) I drove my 2004 Century well enough that I was offered a 2011 glider that was 'supposed' to go to a 3 year driver. He got my truck and I got the 'new' truck. There was a small, but noticeable difference between a DD60 with an EGR and a DD60 without. A year later I went into a Cascadia due to all trainers needing to have a CMS. The Cascadia shifted MUCH differently than either my Century or Columbia Glider. It took a couple weeks, but I adjusted my shift points to coincide to what the truck wanted. It took longer for me to adjust my training to the new engine/transmission, but it happened and my trainees performed better than their peers. Even considering that I'm training new drivers, the fuel usage for my tractor put me in the top 10% of the division. In 2013 I was asked to be part of a fuel economy training video. When I showed up it was me, with 3 years of experience and 3 "Hall of Fame" drivers who had 3 million safe miles a piece. We all did the same route and I KICKED THEIR TUSHIES in both fuel economy and total time. The moral of the story is a driver needs to drive HIS truck based off of HP, transmission, rear axle, and weight distribution.

When you look at the fuel economy scatter plot for 10,000 trucks on DD15 with manual transmissions to DD15 with DT 12s the difference is remarkable. The DT12 gets better fuel economy because it's got 2 more gears, but ignore that and just look at the distribution. With a manual transmission we fit almost a perfect bell curve while with the DT 12 80%% of the drivers are within a 10% differential. The top drivers take a modicum of a dip while average drivers are drawn upwards and the window lickers are trebucheted into efficiency.

 

After a few weeks running my big dislike is the jake brake on this truck. Yeah it's good. Almost too good. In conjunction with that computer controlled auto trans it just goes a little to far.

Like in my old truck if I was coming up on something and needed to bleed off some speed a little jake was all I used. Never touch the brakes unless you have to is kind of a motto for me. Hell the trailer im pulling for 6 years now had all brand new brakes installed back in the spring of 2018 they should be good to go for another 2 or 3 years. In other words trucks I drive dont consume lots of shoes and drums. I use my jake to slow, anticipate a lot, gear down. On this newer truck if you just let your foot off the accelerator with the jake on it'll drop a gear or 2 and the revs will wildly swing up to 2,300 rpms while that jake starts singing then it slows down, a lot. And when you only need to slow down a little that sucks. So much so that I find myself only using the jakes on mountain grades and never any other time.

I use the service brakes a LOT more now. I can see brake shoe consumption on the trailer going up. I guess the discs on the tractor can take it and will still hold up longer than drums? I dunno, that's about the only complaint I have. Not having the finer control of using the jake and downshifting as needed. When I just need a little jake in 12th gear I dont need it dropping to 11 or 10 and revving up the rpms to slow me down quick. Now it works great to stop quickly in a short distance if you need it but I rarely need that.

 

Toss it in manual mode first and it won't downshift you.

On the other hand it's nice leaving the make a on low as you try and stop with heavy loads because the truck will actually downshift intelligently

 

See I haven't even read the manual. Just learned it all on the fly. I'll try that.

 

@rollin coal, what happened to your FLD?

 

A couple of months ago a connecting rod bearing seized. It's a long story, the short version.. I was headed to a delivery in Florida and noticed my engine fan on more than normal, oil temp a tad high and oil pressure about 5 psi below normal. Take the next exit for a truck stop. Looked at it, checked oil. Knew something was wrong. Parked in a spot and unhooked from my trailer.

When the other driver came to get my load and finish it I was showing him how it was running what it was doing. It seized right then and there we heard it chirp and stop. It didn't destroy the block but obviously it's going to cost a #### pile of money to fix properly. I can do a lot of things working on a truck but an out of frame, even and inframe is way beyond my abilities. It's a 24 year old truck. The 1999 ELD exemption is on the chopping block. I've managed just fine on ELD since then. I kind of feel like its time to park it in a fence row and let it rust away.