Thoughts about re-gearing and locker configurations

redneck_adjacent

Active Member
EDIT: I invested in a fully assembled rear differential with an Eaton E-Locker and 4.88 gear ratio. I am, however, still searching for the right setup for the front differential (7.5").

I realize it's ultimately a matter of subjective opinion and driving style but, nevertheless, I would like your thoughts after learning a bit about the problems I have, the driving I do, and the goals I want to realize.

First of all, I drive a 1997 Tacoma DLX 4x4 with a manual W59 transmission and 3RZ-FE with a Magnuson supercharger, cold air intake, and full LC Engineering exhaust.

The problem is that, presently, my gear ratio is 3.58, which is really "tall" especially for 265/75R/16 tires. In particular, it frustrates me how often I must shift into 4 low. I shift into 4 low when I drive at low speeds on steep hills around town. I shift into 4 low when I exit an underground parking lot. Irrespective of incline, my truck "hiccups" in first gear unless I keep the RPM's high. I really, really do not like those things. The supercharger helps a lot; but, of course, it only helps so much. Second, my truck doesn't handle well off-road, which is normal with open differentials but frustrating nevertheless. In addition to logging roads, I would like to take the truck into beginner to intermediate rocky terrain. I don't want this truck to be a full-fledged rock crawler; it's too pretty. However, I want it to be capable on and off-road.

The Taco is my only vehicle. Therefore, drivability matters a lot to me, so a spool and-or detroit locker are off the table.

Right now, I am favorable to the idea of re-gearing to 4.88, getting 33" or 35" tires, and installing an Eaton TrueTrac in the rear. The idea of an air locker does not appeal to me for a lot of reasons: it is expensive; an air compressor eats a lot of precious space in the engine bay or cabin; a switch must be installed in the cabin; and the air line is prone to disruption from debris while off-roading. I am more favorable to E-Lockers but the cost and difficulty of sourcing and installing the parts are strong deterrents for me.

Based on what you read above, would you concur that a 4.88 gear ratio on 33" or 35" wheels is OK, and do you think that an Eaton TrueTrac in the rear is sufficient or should I also consider one in the front, too? Or, do you think my rationale is completely off-base?

Forgive me, friends. I have a lot to contribute when it comes to electronics and engine management; however, my knowledge and experience of drive-trains is weak.

Thank you, friends. I hope you are having a nice day so far.

P.S. I have a friend who is a talented metal fabricator. He will help me trim the fenders and wheel wells when larger tires are eventually installed so don't worry about that part :)
 
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i wish i knew any little thing about this to give some positive input!
but i am still in the amatuer beginner stages i think
 
The only thing I knew about those trucks back in the day is that some came equipped with 31'' tires...they had 4.87 gears in their differential, so you can take it from there.
 
So, All Pro had a stellar deal that I couldn't ignore. They have fully assembled 8.4" rear differentials with Eaton E-Locker available so I pulled the trigger on one with a 4.88 ratio. My primary concern was sourcing an Eaton E-Locker plus the cost associated with assembling it so this really assuaged my concerns. The only challenge now is wiring; but, as it happens, electrical work is something which, for whatever reason, I really excel at.

Obviously, I still need to source a 4.88 ring and pinion for the front, as well as debate the possibility of some sort of locker or LSD, but more to come on that soon . . . . . .
 
Only question I had is, how in the world did your truck end up with 3.58 gears when most toyota trucks as such had roughly 4.00, 4.30, or 4.56?
 
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Only question I had is, how in the world did your truck end up with 3.58 gears when most toyota trucks as such had roughly 4.00, or 4.30?

Humbly, I don’t know the answer to that question concerning how or why Toyota included 3.58 gearing in some trucks. It wasn’t as uncommon as you might (reasonably) expect, though. If you look up one of the many VIN sticker decoding charts then you will learn some trucks had even taller gear ratios than mine (3.58). It gets even crazier when you consider the fact that my truck used 29” tires off the dealership floor.

You should see the looks on people’s faces when I exit underground parking garages without 4 low activated. Unsurprisingly, they think I am a mad man. When I drive around Ballard in Seattle where there are a lot of incredibly steep hills, I can only go about 5 MPH in 4 low which angers everyone behind me.

The Pickup and Tacoma are great trucks but they had some really odd design choices when you think critically about the frames and drivetrain, subsequently forcing customers to make all sorts of modifications. Granted, you see that with every vehicle but it’s nevertheless an odd thing to behold.
 
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I've had toyota 4wd pickups since their inception in 79, and not one ever had a 3.58 final gear ratio. I don't know about 2wd models if the case, or trucks sold in other countries, but the 4 cyl., or 6 cyl. 4wd trucks owned were always 4.10- 4.56's. Even my tundra 4.7 v8 used the same 3.90 gears my current gen3 6 cyl. auto tacoma now has. Their gen3 manual uses 4.30's.
 
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I've had toyota 4wd pickups since their inception in 79, and not one ever had a 3.58 final gear ratio. I don't know about 2wd models if the case, or trucks sold in other countries, but the 4 cyl., or 6 cyl. 4wd trucks owned were always 4.10- 4.30's. Even my tundra 4.7 v8 used the same 3.90 gears my current gen3 6 cyl. auto tacoma now has. Their gen3 manual uses 4.30's.
I guess you were lucky. You seem dubious of what I said. If so then Google it for yourself, like I said earlier.
 
I did, but didn't find anything else related to toyota 4wd pickups that I had owned.....there wasn't any choice in final gear ratios other than I mentioned, unless someone purposely altered them later for their own use. Idk about toyota trucks made to be used in other countries.
 
I did, but didn't find anything else related to toyota 4wd pickups that I had owned.....there wasn't any choice in final gear ratios other than I mentioned, unless someone purposely altered them later for their own use. Idk about toyota trucks made to be used in other countries.
I found this source with twenty seconds of searching online:


There are literally hundreds of other sources as well including official and unofficial ones.

Incredulity is not evidence.
 
Sure, if looking for 2wd pickups, they had different gear ratios than 4wd's, but these are 4wds here.

My truck is 4 wheel drive and came that way from the factory along with a 3.58 gear ratio.

If there is something I don't understand then let me know; but every axle decoding chart I have seen explicitly states that B02A corresponds to 3.58 and I have yet to read anything which says the contrary.

Screenshot 2023-11-28 at 1.23.32 PM.png
Screenshot 2023-11-28 at 1.27.06 PM.png
 
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Its odd. All the ones I've seen here in new england had 4.10 gears. I've spoke with a friend of mine late this afternoon, and from what he's experienced, and found out, the 97 taco was offered with a bunch of different ratios, mostly on their 2.7 2wd trucks. Some 4wd trucks got 3.58 gears, but he hasn't seen any here yet either. Could be the part of the country these trucks were sold.
 
Its odd. All the ones I've seen here in new england had 4.10 gears. I've spoke with a friend of mine late this afternoon, and from what he's experienced, and found out, the 97 taco was offered with a bunch of different ratios, mostly on their 2.7 2wd trucks. Some 4wd trucks got 3.58 gears, but he hasn't seen any here yet either. Could be the part of the country these trucks were sold.

I share your surprise. The truck came with 225/75R/15 tires and 15" wheels which is quite large for a 3.58 ratio.

Not really sure what else to say.
 
EDIT: I invested in a fully assembled rear differential with an Eaton E-Locker and 4.88 gear ratio. I am, however, still searching for the right setup for the front differential (7.5").

I realize it's ultimately a matter of subjective opinion and driving style but, nevertheless, I would like your thoughts after learning a bit about the problems I have, the driving I do, and the goals I want to realize.

First of all, I drive a 1997 Tacoma DLX 4x4 with a manual W59 transmission and 3RZ-FE with a Magnuson supercharger, cold air intake, and full LC Engineering exhaust.

The problem is that, presently, my gear ratio is 3.58, which is really "tall" especially for 265/75R/16 tires. In particular, it frustrates me how often I must shift into 4 low. I shift into 4 low when I drive at low speeds on steep hills around town. I shift into 4 low when I exit an underground parking lot. Irrespective of incline, my truck "hiccups" in first gear unless I keep the RPM's high. I really, really do not like those things. The supercharger helps a lot; but, of course, it only helps so much. Second, my truck doesn't handle well off-road, which is normal with open differentials but frustrating nevertheless. In addition to logging roads, I would like to take the truck into beginner to intermediate rocky terrain. I don't want this truck to be a full-fledged rock crawler; it's too pretty. However, I want it to be capable on and off-road.

The Taco is my only vehicle. Therefore, drivability matters a lot to me, so a spool and-or detroit locker are off the table.

Right now, I am favorable to the idea of re-gearing to 4.88, getting 33" or 35" tires, and installing an Eaton TrueTrac in the rear. The idea of an air locker does not appeal to me for a lot of reasons: it is expensive; an air compressor eats a lot of precious space in the engine bay or cabin; a switch must be installed in the cabin; and the air line is prone to disruption from debris while off-roading. I am more favorable to E-Lockers but the cost and difficulty of sourcing and installing the parts are strong deterrents for me.

Based on what you read above, would you concur that a 4.88 gear ratio on 33" or 35" wheels is OK, and do you think that an Eaton TrueTrac in the rear is sufficient or should I also consider one in the front, too? Or, do you think my rationale is completely off-base?

Forgive me, friends. I have a lot to contribute when it comes to electronics and engine management; however, my knowledge and experience of drive-trains is weak.

Thank you, friends. I hope you are having a nice day so far.

P.S. I have a friend who is a talented metal fabricator. He will help me trim the fenders and wheel wells when larger tires are eventually installed so don't worry about that part :)
I have a 2.7 with 3.5 ratios and 31" tires and I know what you are going through. I can't use 5th unless there is a good tail wind. I had a Detroit locker put in the rear and a TrueTrac put in the front. Really makes a difference when you have true 4 wheel drive. I think your ratios would be perfect. The TrueTrac in both ends would be even better. There are charts that will allow one to figure out your RPMs at a given speed with any size tire with a 1:1 gear. If you have overdrive you can do the math. 4.88 would allow you to use over drive at 70-75 mph with those tires. I wouldn't go with any taller tires since the Toyota axles on the front independent front isn't that strong.
 
I think even these newer 3rd gen automatic trd/sport double cab tacos suffer from having 3.90 axles, especial when guys replace them with larger big ass heavy tires. I've kept my sr5 v6 access cab all stock, and it rips vs these heavier double cab trims. It even tows my 5x10 loaded utility trailer much the same as my gen1 4.7 tundra. Many bitch about the goofiness of these 6 speed automatics, but I love mine...it's buttery smooth with flawless shifts. Imo toyota should of used the same 4.33 gears as they did in their manual tranny models, but thats any story for another time.
 
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