Forum Discussion
40 Replies
- otrfunExplorer II
skyhammer wrote:
The 4.6 is just a 5.7 with a shorter stroke. Toyota saved a lot of R&D money by just taking the 5.7 and shortening the stroke. Although the 4.6 uses a cast-iron block (vs. the 5.7's aluminum), I wouldn't surprised if 90% of the parts on both engines were interchangeable.esjay wrote:
spoon059:
Well, that shows what I know, or don't know. I'm very familiar with the 4.6 if it is the same one that Lexus uses. I was told wrong by Toyota salesmen about the towing package if this is true.
However, 2mpg difference almost makes this a nonissue, especially since the 4.6 requires timing belt replacements. It is one very smooth and refined engine though, so I may reconsider it. Toyota has one of the most confusing websites when it comes to building a vehicle. I'll probably buy a Tundra, then two weeks later discover that a diesel Tundra is on the way soon. Yes, I have read the rumors.
The 4.6 Toyota engine does not have a timing belt, it has a chain like the 5.7. - skyhammerExplorer
drhuggybear wrote:
I have a 2007 5.7L CrewMax pulling a 2013 Crossroads Z-1 (~4800lbs). I have about 200lbs of stuff in the back of the truck. This is a recent (August) acquisition with 4 trips in it so I don't have the best set of data with it but I will give my experience.
As others have said, speed, wind resistance and consistency are what makes or breaks you on mpg. I used to have a Rockwood popup that matched, height and width wise, almost perfectly with the bed of the truck. It was just like adding another 12-14 feet to the bed. Pulling that at 65-70 I could get about 12-13. Since getting the travel trailer I have had to change the driving habits :).
The worst I have seen is 7.8 and that was just about the worst possible conditions. Stop and start traffic, hills, into the wind, raining. Just bad.
Using S-mode, staying below 65 and staying out of passing gear helps the most. I don't have enough Tow Mode tests to know if that impacts all that much. Best I have seen so far has been 9.9. It dropped just below 10 about 30 minutes from home. On that trip I was keeping it right at 65. Now there were times to pass I had to go above 65 for short distances. If I were to lock onto 60 I could probably get 10-11 easy.
Basically its a tradeoff, you go slower and you get better gas mileage. My Tundra, she doesn't like slow ;)
Tow mode does not work in "S" mode.
A quote form the shop manual.
" The conditions required for tow/haul control to operate are as follows:
- Shift position: D position (Tow/haul control does not operate in the S position)". - skyhammerExplorer
esjay wrote:
spoon059:
Well, that shows what I know, or don't know. I'm very familiar with the 4.6 if it is the same one that Lexus uses. I was told wrong by Toyota salesmen about the towing package if this is true.
However, 2mpg difference almost makes this a nonissue, especially since the 4.6 requires timing belt replacements. It is one very smooth and refined engine though, so I may reconsider it. Toyota has one of the most confusing websites when it comes to building a vehicle. I'll probably buy a Tundra, then two weeks later discover that a diesel Tundra is on the way soon. Yes, I have read the rumors.
The 4.6 Toyota engine does not have a timing belt, it has a chain like the 5.7. - drhuggybearExplorerI have a 2007 5.7L CrewMax pulling a 2013 Crossroads Z-1 (~4800lbs). I have about 200lbs of stuff in the back of the truck. This is a recent (August) acquisition with 4 trips in it so I don't have the best set of data with it but I will give my experience.
As others have said, speed, wind resistance and consistency are what makes or breaks you on mpg. I used to have a Rockwood popup that matched, height and width wise, almost perfectly with the bed of the truck. It was just like adding another 12-14 feet to the bed. Pulling that at 65-70 I could get about 12-13. Since getting the travel trailer I have had to change the driving habits :).
The worst I have seen is 7.8 and that was just about the worst possible conditions. Stop and start traffic, hills, into the wind, raining. Just bad.
Using S-mode, staying below 65 and staying out of passing gear helps the most. I don't have enough Tow Mode tests to know if that impacts all that much. Best I have seen so far has been 9.9. It dropped just below 10 about 30 minutes from home. On that trip I was keeping it right at 65. Now there were times to pass I had to go above 65 for short distances. If I were to lock onto 60 I could probably get 10-11 easy.
Basically its a tradeoff, you go slower and you get better gas mileage. My Tundra, she doesn't like slow ;) - esjayExplorerspoon059:
Well, that shows what I know, or don't know. I'm very familiar with the 4.6 if it is the same one that Lexus uses. I was told wrong by Toyota salesmen about the towing package if this is true.
However, 2mpg difference almost makes this a nonissue, especially since the 4.6 requires timing belt replacements. It is one very smooth and refined engine though, so I may reconsider it. Toyota has one of the most confusing websites when it comes to building a vehicle. I'll probably buy a Tundra, then two weeks later discover that a diesel Tundra is on the way soon. Yes, I have read the rumors.
By the way,we want a Limited and the 4.6 isn't even available in the Limited. The 5.7 is standard. - 12thgenusaExplorer
guidry wrote:
I had a 2007 Tundra 5.7 and towed a 27' Prowler with one slide. Truck pulled good but was close to maxed out weight wise. I never had any real issues and towed across the country and averaged 10 mpg towing and 20mpg non towing. I got tired pulling over every two hours to get gas.
But . . . over 200 miles in 2 hrs or 10 mpg at 100 mph? Sounds good to me. ;)
Seriously, my 5er weighs about 8300#, GCW about 14,600# and I keep the speed to 65 unless the conditions or limit is lower. I have over 11k miles towing this combo and have averaged right at 10.5 mpg towing. You should do better than that. - spoon059Explorer II
esjay wrote:
The 4.7 is still available in the Tundra, although EPA is only 2mpg higher than the 5.7. Toyota seems to push the 5.7 for towing, as it is the only Tundra engine that comes from the factory with a complete tow package, 7 pin hookup,etc. The 5.7 is a bit of an overkill for pulling a Casita, but who knows, we may get a larger trailer later (I hope not).
Nope, the 4.7 was retired a couple years ago. They now offer a 4.6 which is much different technology than the old 4.7 was. You can buy a 4.6 with tow package, 7 pin hookup, engine cooler, trans cooler, and trans temp gauge. Only difference between the 5.7 and 4.6 is final drive on the 4.6 is 4.1 as opposed to 4.3. - guidryExplorer III had a 2007 Tundra 5.7 and towed a 27' Prowler with one slide. Truck pulled good but was close to maxed out weight wise. I never had any real issues and towed across the country and averaged 10 mpg towing and 20mpg non towing. I got tired pulling over every two hours to get gas. When I retired last year I got a Chev 3500 diesel and could not be happier! I was a Toyota guy til this Chevy. Tundras pull good but I wanted great.
- esjayExplorerThe 4.7 is still available in the Tundra, although EPA is only 2mpg higher than the 5.7. Toyota seems to push the 5.7 for towing, as it is the only Tundra engine that comes from the factory with a complete tow package, 7 pin hookup,etc. The 5.7 is a bit of an overkill for pulling a Casita, but who knows, we may get a larger trailer later (I hope not).
- TECMikeExplorerEsjay:
Perhaps you remember I responded to your recent thread regarding towing a Casita.
As a follow-up to my response to you in that thread, we have a friend that has towed 17' Casitas for many years with their Tundra. It is an older one with the 4.7L V-8. It is smaller than the current Toyota Tundra and has much less inside cabin space than the larger, newer generation 2014 Tundra.
Our friends always get between 12-14 MPG, towing 60 MPH, depending on wind conditions. This is first hand information as they often travel with us and filled up when we filled up.
The wind resistance on a Casita with its rounded frontal area, sides and back is MUCH less than a conventional travel trailer with a square frontal area. Kind of like a small Airstream.
Having towed travel trailers over 42 years, my wife and I have also found wind resistance, frontal area, and towing speed to be the single largest factors affecting gas mileage.
As I understand the newer Toyota Tundras has a larger 5.7L V-8 engine, so I have no experience direct experience with it. However, I would think your mileage would be close to the previous generation Tundra with its 4.7L V-8 if you towed at 60 MPH as our friends do.
Mike
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