jzack

I understand that more fuel = less engine life. But I also think how a truck is driven can be an even bigger factor. My MPG actually went up a few ticks since turning up the pump. Now I actually spend LESS time in the throttle trying to accelerate or maintaining a cruising speed. I only give it enough to reach max boost and I start backing off when the pyro hits 1000F on long pulls. The only thing that concerns me is the higher factory compression ratio of a 350HP vs. the 400HP and up. So adding 460HP fuel to a 350HP could create even higher cylinder pressures then intended for an E-7 from the factory. But again, excess heat can be controlled by your right foot. Mack engineers have to design their engine packages from the factory to be able handle anything an inexperienced or uncaring driver can throw at it. I, on the other hand, like many O/O am experienced and care about the maintenance of my truck. My E-7 has 790,000mi and 26,000hrs. with out ever cracking a bolt on it other than for valve adjustment. So spending $380 to turn my 350 up to a 450+ on an engine that will need a rebuild at some point anyway was worth risking some engine life in my circumstance. I actually would have traded this truck in for a 427 or 460 if not for the performance gain from the module. The cost of even a 5 year old truck is much greater than a rebuilt engine so the decision was a no-brainer for me. Besides, if I'm getting BETTER mpg with the module, how much harm could it be doing? However, I don't disagree with the overall fact that turning up the fuel can mean shortened engine life in most circumstances. Jeff

Mine had 750,000 un-touched when I added the Blixxton and now has 790,000. Of course adding more fuel probably doesn't extend the life of my moter but the increased power and milaege is worth the trade-off IMO. The nice thing about the Blixxton is it adds more fuel in the lower RPM ranges where the electronic E-7's are usually weak. Probably from EPA breathing down Mack's neck. Although if you are already getting 30+ lbs I'm not certain the Blixxton will help (guessing you have a 427 or 460HP). They were designed to work for the 300HP - 400HP E-7's with the electronic Bosch in-line pump.

I would try both positions and pay attention to your boost guage if you have one. There should be a big difference between the two positions. Mine will run 30PSI on the 30% setting and about 22psi on the 10% setting. My instructions were actually wrong and said the 30% setting was toward the wire when it was away. I was running it on the 10% setting for 3 months before I realized it and WOW what a difference! I'm really impressed with this product. Best $380 I ever spent on my Mack. Your truck still running good with your Blixxton Noid? Jeff

These batteries have the strip caps. Funny thing is all three of them seem to be leaking from under the caps. I'm going to need a battery box soon as mine has a fair amount of rot (14 years of Mn. winters). I would hate to have to put these leaky batteries into a brand new box. Maybe I'll call the manager at Batteries Plus and bug him a little more about this.

My batteries have been leaking fluid into the battery box for quite awhile now. I've checked the voltage at the terminals with the truck idling and I get about 14volts. Thats normal right? I also moniter my volt guage throughout the day and it never reads over 14volts so I don't think they're being overcharged. Yet Batteries Plus where I bought them seems to think the only reason for a battery to leak is over-charging so they won't warranty them. Maybe the caps just aren't sealing properly. Any ideas anyone? Thanks Jeff

I grew up in my Dad's 79 Superliner with a 300+ and Eaton 13sp that had the pull-up style range selecter. Jeff

Thanks Mackpro

Mackdog- Thanks for the tip. I might try wiring in a switch if I cant find the root problem. I've been driving this truck since it was new and I know I used to be able to set idle with the buzzer on. Nice looking wrecker! rw613- I'll try replacing the switch. Thanks!

A few months ago I could no longer set-up my idle when my low air buzzer is on. Now recently I noticed my parking brake dummy light no longer works even with a new bulb. Could these two problems be related? I traced the bulb wire to the senser/sender under the dash above the brake pedal. There is no continuity between the tabs on the senser even with the parking brake applied. Is this good enough evidence to replace the sensor or should I check it with a mult-meter? If so what is the test procedure? Again this is a 94 CH w/v-mac1 and unfortunatly I dont have a code-checker. Any help is greatly appreciated. Thanks, Jeff.

If you are looking to "hot-rod" your E-7 there is a place called Rochester Injector Service that sells bigger injectors and turbo kits. I've heard of some guys getting close to 600HP out of their E7's but I don't know how dependable they would be as a everyday worker. Especially grossing 140K like you are......

Today I put some graphite-oil in every nook and cranny of my steering column and wow, that made a big difference. There is still a little howling, but now its much quieter. Thanks, Jeff.

Thanks for the advice guys. I actually recently took the shaft out to replace both u-joints. On re-assembly I did grease all zerks and packed the slider mechanism. It's not low on PS fluid, however there is a small leak on top of the gearbox at the shaft input. I only need to add oil maybe every 2 or 3 months though. Mike- are you talking about lubing the shaft on the coloumn right below the steering wheel? Maybe I'll try that.

Just recently my steering wheel has started howling or whining during slow turns. Used to only do it when hitting the left or right lock. Can anyone tell me what causes this and if I should be concerned? Thanks, Jeff.

Thanks Glenn. So 4valves have more power but 2valves are indestructible. I'm assuming most recent diesels (i.e. E7) are all 4valve. Right?

Could one of the great Mack experts on this site please explain which Mack motors came with 4v or had the 4v option. What's the difference? Is it like gas engines where the 4v is generally more efficient. I'm specifically interested in the E7's. I currently own a 94 E7 350 and am looking at a 93 E7 350 where the owner lists it as a "350 4valve". The 94 is electronic while the 93 I believe is mechanical (if that makes a difference). Any help is greatly appreciated!

94 E-7 350HP w/Blixxton module. Pulling flat-bed empty on return trips-- 7.4 MPG