96 Taco Build/Discussion Thread

[ps2fixer]

Settled on the 235/85/16 ironman tires, which are made by Cooper. The brand had good reviews on other tires, but couldn't find any for these exact tires. Oddly I found a lot of people had issues with the BFG's. I also picked up a set of 4runner rims with 3 good tires to resell for $60. Same style as my truck came with, except 16 inch .

Anyway, I got to trail ride my truck for the first time yesterday, did great! I could probably have just left it in 2wd in the snow and did find with my crappy street tires that are bald.

For the transmission fluid, transfercase, and axles I'm going to go with Red Line. From research, ANYTHING todo with transmission issues and such people suggest red line and report with with great results. Amsoil, royal purple, and mobile1 are all good fluids, but none of them helped with shifting problems and such. Interesting read since the red line 75w rate gear lube is about as thick as motor oil, I think the one use was guessing around 10w30, that should help a little with mpg.

Since I have been driving my truck, I found there is for sure some sort of lube issue with cold weather, I suspect someone put in too thick of fluid. I can feel it dragging me down till everything warms up in a good 15 miles or so. My truck is a bit hard to shift into 1st when it is cold so I'm hoping the red line will help with that too.

Still no photos, I'm slacking!

[ps2fixer]

Yesterday morning I threw in my scan gauge 2 and drove "normal" to work and it indicated 20mpg, on the way home I played around with speeds, gears, etc to see what effects what. 55mph on the express way and 45mph on the back roads netted me 22.5mpg for the trip home which normally is worse. That is WITH 4x4 usage due to slick roads on the way home. When I put it in 4x4, the mpg dropped about 12%, but I do have a miss matched tire in the front, and I suspect that is causing some extra drag. I'm thinking manual locking hubs would really help when I don't need the 4x4.

Anyway, last night I took the mechanical fan off and removed my grill block. No fan currently, but I have extremely little city driving, only 4 stop lights. I plan to install an electric fan before spring hits.

Hopefully the scan gauge says my mpg increased today, I'm sure it will since I'm going to leave a bit early and go slower.

Just some fun numbers (purely from memory before any mods but the grill block)

70mph warmed up - 19-21mpg
55mph warmed up - 22-25mpg
55mph cold (first ~10-15 miles) - 17-20mpg
45mph warmed up - 24-26mpg
35mph warmed up - 28-31mpg

MPG figures are not calibrated! But the % differences should be semi accurate.

[ps2fixer]

Another update on the Taco. I picked up another set of 16in rims with 265/75/16 tires on them in fair-good shape with 1 junk, but I have a spare tire that is the same. Popped them on, adjusted the brakes up, one side the adjuster was hung up so that should help it work better. Front end spinning the tires with the trans in 1st is hard! lots of resistance, rear tires are nice and easy to spin. I wonder if the front diff is a limited slip or something. Anyway, both front tires are the correct size now, and I found the old tires were only around 20psi. "New" tires are at 55psi (50 max side wall), and what a difference in feel, ride, and take off. Also found the right rear leaf spring is broken, 2nd from top and the same side's shock is completely blown out. Drivers side is working but looks OEM with 225k. Engine oil has a red color to it, so I suspect there might be a mix of oil + trans fluid in it. Adjusted the scan gauge at +5% and is now my speedometer. Short trip around 7 miles and back messing around figuring out how far off everything is and such with a GPS and idling a bit got me around 22.5mpg, way back was 24.5mpg. ~8 miles back to my house was 24.4mpg. Short trips seem to be a LOT more mpg, since to trip to my dad's house was 17.5mpg. All trips were with warmed up engine (150f+).

Also no fan has been no problem at all. Highest temp I have seen while driving was 202F when I coasted off the highway and took off up a hill over the overpass. I took it out in my woods a bit and sat idle for around a min, and saw 206F as the peak and it cooled right back down to 200F by the time I got back to the road going 10mph no grill block.

Trans and Diff oils should be in before long, really hoping the Red Line will be a positive switch for better mpg and still protect everything well. Engine oil will be Mobile1 advanced synthetic 5w30 (15k miles for oil change guaranteed). I ran 18k miles on my corolla on the standard mobile 1 full synthetic, and the oil came out dark (not black), but still not bad so this next step up (highest they offer I think), should be good for the truck.

I suspect 30mpg is very reachable with my situation of work being quite a drive away and the mods to the truck so far and it's winter! No areo mods yet since I took the grill block off for safety. Maybe in the spring I'll look into making a belly pan, not real sure on the material, but I'm thinking fairly thin steel kind of like skid plates. Not trying to add 500 pounds to the truck and I'm not sure on chloroplast for the truck, the carolla's 1/2 front belly pan has been bottomed out a couple of times and it don't really like it much lol.

[ps2fixer]

Well, success story, left late for work, so 60mph back road and 70mph on the highway. Pulled into work with an indication of 22.5mpg, which is about the same as my best with the old tires. On the trip home I did 60mph highway, and 45 back roads, pulled in the driveway with an indication of 27.2mpg . At speed 45mph is 30-31mpg, so I think I did pretty good for what my mods are so far. Fill up in in 1-2 more work days.

[ps2fixer]

Scan gauge was giving too high of numbers, unless I didn't have it in the truck since the last fill up. Was around 10% too low for the fill up. Est (tire change in the middle of the tank) was 21mpg. Last few days been getting 22-24mpg to/from work according to the scan gauge. I'm wondering if the tailgate up/down rumor would prove good in my case with a shorter box, guessing not but I'm thinking about trying it for a day.

I received my new 235/85/16 tires, so they should be on the truck before long, and the scangauge will be off once again lol.

With small amount of research, posts suggest that the supercharger option for this engine increases mpg slightly (1-2 mpg claimed). Nothing special, but the extra power for the once in a while fun factor might be worth while. Down side is the rebuild every 100k miles (~4-5 years for me) but +75hp is nice .

Really need to get a notepad in the truck so I can start my fuel log.

[aardvarcus]

Lots of info, here are a couple of my thoughts from your posts.

I also live in the country and use a truck as a truck.

Running mismatched tires in 4x4 is bad in a typical truck, because your transfer case doesn’t have a differential (unlike your axles), thus the difference in diameter forces one or more tires to constantly slip. This is hard on your transfer case. (I know you already got new tires since you posted that, just wanted to mention it for others reference.) You may want to find a used 235/85R16 to have as a spare tire.

As for the hard to spin tires, are you sure your calipers aren’t dragging slightly? You may want to get out and feel your wheels after a long drive for heat.

As for your engine oil having a red tint, are you running red coolant? It would seem more likely to me that coolant and oil are mixing than transmission fluid.

Instead of running no fan, you should consider getting a junkyard electric fan for cheap and wire it up to a switch in the cab. That way you can have a fan that you can switch on for when you have to idle the truck. I will admit I am a bit paranoid about cooling after spending multiple thousands of dollars addressing issues with my older trucks that looking back now would have been prevented by less than one hundred dollars worth of cooling parts that I ended up having to buy anyway.

The electric fan would also be useful for off-roading, if you drive for long periods in low range (too slow for much natural airflow) you could leave the fan on. A used fan would be cheap insurance against a motor overheating. I have an electric fan from a V6 Camry that I am going to swap into my Tacoma.

I will admit I am skeptical that forced induction by itself would increase the MPG of a gasoline truck engine. Forced induction usually accompanies other upgrades (headers, intake, custom ECM tuning, etcetera) that I would think would have more of an effect. Conceivably a truck that had been heavily modified (excess weight, excessively large tires, excessive wind drag) to the point where the V6 was struggling to keep up or being lugged could benefit from the extra horsepower, but I am not so sure about a stock-ish truck. Not saying it isn't true, but I am skeptical.

If you get paper receipts from your fill ups, just write the mileage on your receipts and you have an instant fuel log. Save your receipts until you have time to log or upload the MPG data, and then throw them away.

Oh and pictures are always appreciated.

[ps2fixer]

Thanks for the reply, as for the transmission fluid in the oil, I was meaning someone might have put trans fluid in it to clean out the engine which is a commonly known trick at least in my area. Coolant is Green, I'd NEVER run anything else!

I do plan on putting on an electric fan, I have a couple laying around from older cars, but I'd prefer to stick with ones that came with a Toyota due to their known reliable electronics. The highest I have had my temp empty is 202F which is the same as when I had the fan on it engine.

The supercharger was designed by toyota's racing division (TRD) and the supercharger is a bolt on option that gives 75hp increase, headers, 7th injector etc are other mods that can be done that also increase power output, but headers lower low end grunt a bit, so I'd be sticking with the stockers.

Front calipers could be hanging up, I haven't had much time to dig into it. I just picked up another parts truck with manual lockouts, so most of the front end parts are going to be swapped out when I get some more time .

Speaking of that, picked up a 1999 tacoma, base model, automatic 2.7L for parts (was hit in the rear by a beat truck). I was pressed for time, so going the ~100 miles I was speeding a little and got 18mpg empty (65 highway, 60 back roads). With the truck on the back I got 15.4mpg going 45-50mph back roads and 55 highway.

[mikeyjd]

Originally Posted by ps2fixer

Scan gauge was giving too high of numbers, unless I didn't have it in the truck since the last fill up. Was around 10% too low for the fill up. Est (tire change in the middle of the tank) was 21mpg. Last few days been getting 22-24mpg to/from work according to the scan gauge. I'm wondering if the tailgate up/down rumor would prove good in my case with a shorter box, guessing not but I'm thinking about trying it for a day.

I received my new 235/85/16 tires, so they should be on the truck before long, and the scangauge will be off once again lol.

With small amount of research, posts suggest that the supercharger option for this engine increases mpg slightly (1-2 mpg claimed). Nothing special, but the extra power for the once in a while fun factor might be worth while. Down side is the rebuild every 100k miles (~4-5 years for me) but +75hp is nice .

Really need to get a notepad in the truck so I can start my fuel log.

Tailgate up vs down isn't likely to be a large change in drag, but everything I've seen in the past indicates tailgate up should offer a slightly better trailing wake.

I could be wrong, but I was under the impression that the supercharger would create a less efficient bottom end torque curve in exchange for more top end power. I look forward to your results.

I also experience a 10-15% decrease in FE with 4x4 engaged. It's worth every penny when you need it though (which has been allot around here the last few days).

[ps2fixer]

With winter here, it is pretty hard to tell the effects of things, so I'll probably have to wait till around spring time for the tailgate test, but I suspect either way it won't effect it much.

The 10-15% drop I saw in FE with 4x4 on was with the odd ball tire up front (larger), low tires, and driving though snow. Now with all the same sized tires and tested on clear roads, I don't really see a change. The catcher with how my truck is setup, the front wheel hubs are direct locked in all the time so my front diff is always spinning. I'm sure once I get the manual lockouts swapped over that I'll see a new gain while in 2wd .

I haven't drove the truck much, but it seems FE hasn't really changed except in the distance before I'm getting warmed up numbers. I might be getting slightly better MPG while cold. I have not changed the trans / transfer case fluids yet, hoping to within the next week or so.

I won't have any SC numbers for a long time, I have a couple of other projects that need the funds before the SC. The claimed numbers were from sites where people are looking to either make their trucks fast or go though more mud, so their numbers are probably nothing special to go by, one claimed a drop 1-2mpg, and 2-3 claimed either no change or a slight increase. Depending how things go, I might get a Camry v6 manual and do an engine transplant into it with another Tacoma/4runner 3.4L . According to my research the swap is a mechanical direct bolt in, electronics are another story though.

Also question for ya mikeyjd, I see the last 3-4 tank fill ups are a steady increase in MPG, the temp hasn't done the same thing, so what are you doing different? I'll take a stab and guess you were P&G, seems my truck loves predicted stops, MPG before the coast vs MPG after up to speed is always higher after the stop for me.

[mikeyjd]

Originally Posted by ps2fixer

With winter here, it is pretty hard to tell the effects of things, so I'll probably have to wait till around spring time for the tailgate test, but I suspect either way it won't effect it much.

The 10-15% drop I saw in FE with 4x4 on was with the odd ball tire up front (larger), low tires, and driving though snow. Now with all the same sized tires and tested on clear roads, I don't really see a change. The catcher with how my truck is setup, the front wheel hubs are direct locked in all the time so my front diff is always spinning. I'm sure once I get the manual lockouts swapped over that I'll see a new gain while in 2wd .

I haven't drove the truck much, but it seems FE hasn't really changed except in the distance before I'm getting warmed up numbers. I might be getting slightly better MPG while cold. I have not changed the trans / transfer case fluids yet, hoping to within the next week or so.

I won't have any SC numbers for a long time, I have a couple of other projects that need the funds before the SC. The claimed numbers were from sites where people are looking to either make their trucks fast or go though more mud, so their numbers are probably nothing special to go by, one claimed a drop 1-2mpg, and 2-3 claimed either no change or a slight increase. Depending how things go, I might get a Camry v6 manual and do an engine transplant into it with another Tacoma/4runner 3.4L . According to my research the swap is a mechanical direct bolt in, electronics are another story though.

Also question for ya mikeyjd, I see the last 3-4 tank fill ups are a steady increase in MPG, the temp hasn't done the same thing, so what are you doing different? I'll take a stab and guess you were P&G, seems my truck loves predicted stops, MPG before the coast vs MPG after up to speed is always higher after the stop for me.

I haven't been towing the trailer as much lately. One of my business ventures is buying and selling used appliances. I had been using the trailer quite a bit for a while, often totally full of scrap. Recently I've joined forces with a scrapper, in a mutually beneficial exchange. As he brings them to me and I give him several peices of scrap for his more desirable machines. That way I don't have to deal with scrap runs and can make more for my time. As an added bonues, I avoid bad roads with a full trailer and can maximize my tanks. I still have to use the trailer at times for larger deliveries (only once this last tank), but the difference in FE is substantial. With 4x4 and a fully loaded trailer and bed on snowy roads I get about 16mpg instant on flat. When empty the roads are clear and I can pulse and glide I can usually get 30+ on my trips, since I rarely drive less than 20 miles 1 way.