[Jpeterferrell]

My snowmobile/ski resort cruiser is nearing completion (a 2004 Sequoia Limited 4x4, w/265k on the clock), and having been on a half-season of test runs through the Rockies, I think I've narrowed down my final two problems. One is completing some suspension work, which I'll get to in a different post. The other is a not-uncommon automotive problem - lack of power. I am regularly crossing mountain passes at 10,000+ feet. At that altitude, the truck has a ~30% reduction in available power. I'm not towing anything, but I do sometimes have a full vehicle (4 adults, 2 kids, ski gear). Needless to say, in these situations, the truck feels like it is struggling, often downshifting to 2nd to get up and over the passes.

I have stock diameter wheels/tires (slightly narrower than stock actually, for better snow performance). I have no other power-adders other than the JBA short-tube headers. The truck runs perfectly otherwise - regularly returns 16-20 mpg if I drive without a lead foot, and even consistently gets 18 mpg when going over the mountains. I don't worry about fuel economy. I worry about durability and reliability, but I want to make going through the mountains easier.

The three options as I see them are this:

1) Find and install one of the rare TRD supercharger kits (I think I could do this myself)
2) Custom rear-mount turbocharger setup, running ~5 PSI. No intercooler (shop)
3) Re-gear to 4.56 or 4.88 (shop)

In my mind, option #3 sounds like the most reliable and cost effective way to squeeze out some more relevant, mountain-crossing power, at the expense of fuel economy (don't care) and some RPMs (also don't care). Any other ideas...?

 

[SilverSasquatch]

Shifting to second is normal for these transmissions. The torque for the 2UZ engines is higher in the RPMs, so the trans has to drop it into 2nd. Mine does this over small hills while in cruise at highway speeds. I also shift it into 2nd coming off of cloverleafs to get it up to speed.

 

[bruin]

What if you regeared the transfer box?

Does anyone do that? Might be cheaper than regearing two differentials

 

[flighht2k5]

What if you regeared the transfer box?

Does anyone do that? Might be cheaper than regearing two differentials

You can’t re-gear the transfer case. Having a lower low range wouldnt help

 

[Jpeterferrell]

Cost to re-gear the front and rear is something in the $2k range. If I did the install of an Eaton TrueTrac in the rear at the same time (something I’ve been considering doing) that goes up to ~$2.5k. Cost of a TRD supercharger install is probably in the $5k range. Custom turbo kit (rear mount, low boost, no intercooler), something like the old STS system, probably in the $7k range.

I’m going to run some numbers and see what a re-gear to 4.56 will get me as far as additional torque at the wheels...

 

[LookingUp]

Cost to re-gear the front and rear is something in the $2k range. If I did the install of an Eaton TrueTrac in the rear at the same time (something I’ve been considering doing) that goes up to ~$2.5k. Cost of a TRD supercharger install is probably in the $5k range. Custom turbo kit (rear mount, low boost, no intercooler), something like the old STS system, probably in the $7k range.

I’m going to run some numbers and see what a re-gear to 4.56 will get me as far as additional torque at the wheels...

I know you've done a lot of work to the truck but you're talking about a significant investment on a vehicle that probably has a KBB of like $6,000. If you want more power than you probably need to look at a GM SUV (escalade/denali). With the numbers your throwing around I think it might also be reasonable consider an LS swap with a built 5.3 or 6.0. The reality is that these 4.7 motors will not make big power and there really isn't much left on the table from factory.

 

[Jpeterferrell]

I know you've done a lot of work to the truck but you're talking about a significant investment on a vehicle that probably has a KBB of like $6,000. If you want more power than you probably need to look at a GM SUV (escalade/denali). With the numbers your throwing around I think it might also be reasonable consider an LS swap with a built 5.3 or 6.0. The reality is that these 4.7 motors will not make big power and there really isn't much left on the table from factory.

That's a very good point. I think for the moment it may be best to just do some small things (12-hole injectors, maybe a bit better exhaust), and not worry about the truck having to do a lot of shifting at or near the mountains. At some point maybe I'll put it on a dyno and see just how far off from stock I actually am (if at all). The excellent fuel economy (all things considered) does lead me to believe the 4.7 is running about as well as can reasonably be expected. I also imagine some of my annoyance is that shifting at this point is a bit...abrupt. The transmission still holds fine, no overheating, but it's definitely not smooth. It makes the downshifting more disconcerting than it probably should be. Maybe my $$ is better put towards awaiting a transmission replacement with a low-mileage unit!

 

[anilkan]

What if you regeared the transfer box?


Speed Test

 

[Rayland]

I have the original TRD Supercharger on my 2002 Sequoia. When TRD stopped the supercharger program a few years ago, Magnadyne started doing it and some Toyota dealers are now Magnadyne dealers also. You may go on their website and see if they make one for the older models. I have 234000 miles on my TRD version, no other power mods and have loved it for trailer towing. The only issue I have had with trailers is it still strains at interstate speeds on tall box trailers due to wind resistance above 65 mph but it laughs at low trailers even when loaded to 5500-6000 pounds (ie hauling 1972 Mercedes SEL on car hauler).

 

[Robbobbert1]

I have the original TRD Supercharger on my 2002 Sequoia. When TRD stopped the supercharger program a few years ago, Magnadyne started doing it and some Toyota dealers are now Magnadyne dealers also. You may go on their website and see if they make one for the older models. I have 234000 miles on my TRD version, no other power mods and have loved it for trailer towing. The only issue I have had with trailers is it still strains at interstate speeds on tall box trailers due to wind resistance above 65 mph but it laughs at low trailers even when loaded to 5500-6000 pounds (ie hauling 1972 Mercedes SEL on car hauler).

How many pounds of boost? 91 or 87 octane? No transmission issues with 02?