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Extended High RPM Cruising

firecadet613

By firecadet613
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firecadet613 Enthusiast

firecadet613

Posted
Posted

Say I'm turning 3500rpm on my 4.3 v6 in the truck shown in the sig for a few hours while towing, will that do any harm to my motor or anything? Redline is at 5k.

 

Joe

bowtie_pasta Enthusiast

bowtie_pasta

Posted
Posted

Even though it's not near redline, that's still pushing the rev's imo. Assuming all basic maintenance items are taken care of I'd think you'd be ok. I'd just hate to wring that engine at 3500 for hours on end.

 

Roland

firecadet613 Enthusiast

firecadet613

Posted
  • Author
Posted
Even though it's not near redline, that's still pushing the rev's imo. Assuming all basic maintenance items are taken care of I'd think you'd be ok. I'd just hate to wring that engine at 3500 for hours on end.

 

Roland

Thats my school of thought as well Roland, even though its not near redline, it's still pretty high, and I definatly don't want to damage my brand new motor.

 

Joe

The SPEEDY Senior Enthusiast

The SPEEDY

Posted
Posted

My celica that I used to drive would turn 3K at 70, and I would take trips to houston turnning anywhere from 3-4k RPM (5k redline). It never minded that at all. Stop and go is what killed it.

 

The 4.3 is a d**n good motor, if it is in good working condition you shouldn't have any problems.

422 SS Enthusiast

422 SS

Posted
Posted

Don't worry about it,your not hurting anything.A friend of mine has a 98 3500HD box truck that he uses for work.The truck has a 454 with a 5.13 gear that spins 3500-4000 rpm on the freeway.It has 150k on it and other than sucking down massive amounts of fuel(5-6mpg) its like the Energizer bunny.Just do your regular maintenance and hammer down.

firecadet613 Enthusiast

firecadet613

Posted
  • Author
Posted

Just what I wanted to hear :mad:. My brother who's an electrical engineer but drives Fords told me it's a OK as long as I'm not near the redline. His trucks are all OHC so I wasn't sure if the same applied to me. I'm staying up in Evergreen Colorado now and make the drive down and up the mountain to Denver daily, but I'll be moving to Indianapolis next week and I might have to run it with OD off the entire trip due to what I'll be towing, but I can't possibly go 55-60 lol.

 

Joe

MCourson Senior Enthusiast

MCourson

Posted
Posted
Awesome, how many miles were on that when you sold it/it died?

 

Joe

If I remember correctly, he had well over 200k on it when it died.

Wingnut Senior Enthusiast

Wingnut

Posted
Posted

Well......Umm....How much are you towing?

 

Kind of a factor in how hard it's working to stay at 3500, right?

 

3500 rpm under a light load should be fine, but put around 6k lbs behind it, and you might be in for an expensive trip.

 

Just my .02

The SPEEDY Senior Enthusiast

The SPEEDY

Posted
Posted
Awesome, how many miles were on that when you sold it/it died?

 

Joe

If I remember correctly, he had well over 200k on it when it died.

Speedo broke at 316K, motor died inbetween there and 350K.

Black02Silverado Senior Enthusiast

Black02Silverado

Posted
Posted

My old 93 sonoma had the 4.3 and it had 128k on it before I traded. It spent most of it's life on the interstate cruising at 3k RPM's. It ran great and strong as can be when I sold it.

 

I think if you keep the maintenance up and a good quality oil and filter you will be fine. The 4.3 is pretty much bullet proof IMO. The boat 4.3's have roller cams, not sure when and if they installed a roller cam in the auto 4.3's. I know I cruise for a few miles in our boat at 4k with 5k being red line and it runs great. :thumbs:

robsawatsky Enthusiast

robsawatsky

Posted
Posted

A 72 Chev 1/2 T Pick-up truck with a 350, 4.10 rear-end, and a 3-speed auto (remember no lockup of TC) was doing about 3300 RPM at normal (i.e. 60 MPH) highway speeds. It redlined at just over 90 MPH. My dad's truck I abused in my early years of driving.

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