rodriguez7

I will be pulling my toy hauler into the mountains this next week. Just wondering if the 4.2 has to much timing for towing heavy.I usually run it on level 5 with my mp-8 up around 40%. Trailer is around 8000 pounds loaded. Thanks

kuhkuhkyle

Do you run the MP8 at 40% all the time? If you do , all that added pressure will likely crack an injetor in time. I tow on level 3. Its got the added power I want but EGTs are managable. Thats on 4.4 tough as well.

JJPage

I don't believe your SPS 62 will keep the egt's in check on sw5/4.2 in the mountains towing that heavy. I would say sw3 max, from my experience, and that may be too much fuel with the 4.2 software.

I just towed over 3 major mountain passes here in the northwest on sw3 Standard Revo. I was about 4000lbs heavier than you are going to be, but I did reach 1250* for some pretty hard long pulls.

I have all the betas, and have pretty much sampled them in many different driving conditions, I believe you would be much happier towing with the 4.4, and I would still limit it to sw3, until you can verify that you will be able to keep your egt's safe.

It gets frustrating having to back out of the throttle and or downshifting on a grade just to keep your egt's in check, a year ago I pulled my 5vr in the mountains when I had a Silver62, never again, could not adjust my fueling to satisfy the load, too little fuel and it was a laggy dog, too much it was hotter than heck, could never get the right combination. Plus the wife was getting irate, are we on vacation or are you tuning your truck?

I did have an SPS62 before the Silver, it did much better towing but still had it's limits.

rip 112

I wouldn't run the 4.2 at all on a towing trip, sw 5 on the 4.2 is close to sw 7 of the 4.4. If you're gonna run any beta program towing, it needs to be the 4.4, the 4.2 has too much throttle, it will strain things when the turbo doesn't spool instantly.

rodriguez7

Any one have the 4.4 file they can email me?