Topic: Tacoma re-gearing

[854RUN]

Ok so the wife has an 02 Tacoma extended cab with a 3.4l, auto tranny, DD, pulls a trailer every now and then (1200 to 2000lbs). She has 285/75/16 on it now with stock gear's. it has lost some power do to that but now she is going up to 35's and i was thinking of re-gearing it to 4.88. What do yall think? I would hate to pay for 4.88's and then find out i should have went with 4.56's. thanks for your input 

[DCabTaco]

if you will be towing 4.88s with 35s are good.  That is what I am running and got most of my power back.  However, you will be slghtly over geared compared to stock, so your speedometer will be about 6 % off in the opposite direction from where you are now.

The real question is how do you plan on making those 35s fit?  I'm assuming you already have some sort of a drop bracket lift or a sas?

[854RUN [OP]]

Cool that just what I'm wanting to hear some real world feed back. What about highway speeds 75mph, what are you rpm's like (not towing).  Ya she has it lifted 5.5", we plan on doing a sas next your.

[Huhwhye]

The auto has a really deep overdrive. .70: compared to .83:1 in the manual trucks.  So you can go with a lot more gear with an automatic and be ok on the freeway.  I'd say 5.29's with 35's, and 4.88's with 33's on a automatic truck to keep it in the powerband better.

Marlin has a speed and rpm calculator off his main page.  Plug in tire size, ratio, rpm and get speed.  Remember your overdrive is .70:1 here is the link link to marlin speed calculator

Stock gears are 4.10's with the automatic trucks (5spds get 3.91's) and I think it is under geared.  All the automatic Taco's I've driven have problems hunting between 3rd and 4th because the big overdrive puts the engine out of its narrow powerband.  Towing and driving on hills makes this worse and I'm always manually shifting it out of OD to keep it from hunting. Getting the revs up a bit won't hurt mpg and will help the power out a lot.  It's a Toyota so cruising at 2700rpm is no big deal at 75mph.  ~2700rpm = 75mph with 35's and 5.29s.  ~2500rom = 75mph with 35's and 4.88's.  I doubt the extra 200rpm will hurt mpg.  It might actually help with the extra drag of the lift and tires.

FWIW...  A 5 speed Taco with 3.91's is at 2650rpm at 75mph.  The 4runner with a 5speed has 4.10s as stock gears.  So with a stock 4runner 2800rpm is 75 mph.  So cruising at 2700rpm with your auto is no big deal.

[854RUN [OP]]

Thanks for all the good info Huhwhye and the link that helped out a lot. I had no idea that the OD was .70:1 i figured it was at lest .80:1 thank for telling me that. I think we will be putting 5.29 in now   

[DCabTaco]

I don't know about 5.29s.  I would stay with the 4.88s personally.  I had 33 with stock gears and didn't like the loss in power.  I then regeared and stayed with 33 for a while, but gas mileage sucked even more on highways.  RPMs were bearable, but just seemed a little too high for me(maybe cause I was use to the stock gears and 33s).  I then switched to 35s and everything went back to normal.  Going up mild hills is no longer a fight for my tranny as it did when it had 33s and stock.  I don't have to have the ECT button on all the time anymore. 

Mileage wise,
I would get about 16-17 stock(heavy foot does that)
33x12.5s and stock gears I would get 13-14 (corrected)
33x12.5 and 4.88s I would get 12-13(corrected sometimes as low as 10-11 but then I started driving slower)
35x15.5 and 4.88s I now get 14-15(corrected but not having to watch how I drive)

You want real world experiance, that is as real world as you can get.  I don't drive my truck to much, but when I do I keep a close eye on the mileage and write it down to see what mods affect it more.  By going to 33x12.5 affected it more than adding the supercharger.  Regearing to proper matching gears helped a ton.  As far as power for towing is concerned, you'd be better off going with 4.88s with the 35s and getting a second set of 33 strickly for towing to help your engine and tranny when it needs it.  just my 2 cents.

[854RUN [OP]]

O You have a s/c. that why the 4.88 work for you. My wife Tacoma dose not have a s/c if she did i think 4.88 would be good. I have 4.88 in my t100 with a s/c 3.4l and 37", and i works great, at 75mph my rpm are at 2800 to 2900. The s/c makes a big difference. 
 

[Huhwhye]

I don't know about 5.29s.  I would stay with the 4.88s personally.  I had 33 with stock gears and didn't like the loss in power.  I then regeared and stayed with 33 for a while, but gas mileage sucked even more on highways.  RPMs were bearable, but just seemed a little too high for me(maybe cause I was use to the stock gears and 33s).  I then switched to 35s and everything went back to normal.  Going up mild hills is no longer a fight for my tranny as it did when it had 33s and stock.  I don't have to have the ECT button on all the time anymore. 

Mileage wise,
I would get about 16-17 stock(heavy foot does that)
33x12.5s and stock gears I would get 13-14 (corrected)
33x12.5 and 4.88s I would get 12-13(corrected sometimes as low as 10-11 but then I started driving slower)
35x15.5 and 4.88s I now get 14-15(corrected but not having to watch how I drive)

You want real world experiance, that is as real world as you can get.  I don't drive my truck to much, but when I do I keep a close eye on the mileage and write it down to see what mods affect it more.  By going to 33x12.5 affected it more than adding the supercharger.  Regearing to proper matching gears helped a ton.  As far as power for towing is concerned, you'd be better off going with 4.88s with the 35s and getting a second set of 33 strickly for towing to help your engine and tranny when it needs it.  just my 2 cents.

OK, but same truck, same tires, same lift there is not going to be a big difference between 4.88's and 5.29's.  Only 200rpm at 75mph is not going to change much.  And around town it might help lug around all that rubber.  I'll take the extra gear, especially since  they tow with it.

In my 4runner I'm running 4.56's and 32's, soon to be 33's.  I'm at 3000rpm at 72mph and I still get 19mpg cruising at 3000-3200rpm, only a loss of 1mpg over stock gears, tires, and no lift.  I think I have a little too much gear right now, but the truck is happy cruising all day at 3000rpm.  It's a toyota.  I think 33's will be perfect and don't expect to loose any mpg.

The higher rpms don't really hurt mileage.  It's all that drag from the lift and tires.  And that automatic needs all the help it can get with that .70 overdrive and wide gear spacing.