Sammer

1. My truck (1993 4Runner) which I just bought, had 31 x 10.5 inch tires on i when I bought it. I have never driven a 4Runner before, and it seems like it has a real hard time going up the hills. Anyways, the door jamb sticker says my stock tire size is 225/75/15...but my owners manual says all V6 4Runners came stock with 31's. Which is right? I can imagine the truck would feel underpowered if it had oversized tires on it.

2. Were there different gears used depending on what size tires were put on at factory? Can i fit the 31 gears in the housings if my stock size is 225/75?

3. Sometimes when I'm going up steep hills, and I put the accelerator all the way down, the truck doesn't downshift. This is kinda annoying because I watch my speed trail off, and con't do anything. ALSO if I turn off the OD, my revs drop...like it shifts up when I turn off OD. What the deal?

4. Does anyone else smell burning metal when climbing really steep and long hills?

5. Oh ya...what does SR5 mean?

Thanks in advance guys...I'm new to these trucks, but I love mine already. Great site!

2ToyGuy

Sounds to me, and I am NOT an AT guy, like your tranny is low on fluid, or needs to be flushed and refilled. I mean really flushed, and the filter changed/cleaned. Not just a drain and refill. But check the fluid level first and foremost. If it's low, you may be screwing your tranny up unnecessarily.
You shouldn't smell hot metal at ANY time. It's a definate sign of a problem. When you take the OD off, the revs should jump UP, not down. Another definate sign of trouble.
The tires on your truck aren't bigger enough (that sounds odd...) to cause these problems. Not to the extent you are seeing. You definately have a problem in the tranny, and need to get it fixed asap.
SR5 is Toyota's way of saying "fancy options pakage". I don't know that the initials actually translate to real words, but that's the general idea. Your 31's may have come as part of your SR5 package, I'm not sure.

4Crawler

iTrader: (3)

SR5: http://www.sr5.net/sr5_sr5.htm

Gears vs. tire size:
http://www.4crawler.com/4x4/4R_TechI...tml#DiffRatios

For 31s, the factory A/T gearing was 4.88.

2ToyGuy

Well, I'll be, I always wondered if it really meant anything! Thanks!

marko3xl3

1. It's normal for trucks to slow down on hills, it's only a 3.0 V6 . As far as I know, the 225 size was the standard, while the 265 size (31") was the optional size; I think it's always been like this.

2. I don't know about second gens, but in third gens, they always came with the 4.10 even with the 31". If you had the factory optional rear e-locker, you sometimes got 4.30 gears, just depends. Maybe 4Crawler is right though, it's 4.88? Sounds a bit too much for 31" though.

3. About your shifting deal, that's also normal. When you are going highway speed up a hill you are most likely going at high rpm's and third gear with the torque converter un-locked/enabled. What happens when you floor it then is that the transmission won't downshift at all to protect itself and the engine (even if you shift into "2"). Now, when you press the OD button while going in 3rd already (at fast speeds), the said un-locked torque converter will lock and rpm's will go down accordingly (so will speed). I am not sure why the TQ does that, maybe because the tranny thinks it's in 4th and thinks it's downshifting so it locks the TQ so that the rpm's don't shoot up as much since the torque converter does add a 1.3 ratio to the overall ratio. I hope you understood all of this .

4. Burning metal is BAD. Make sure you get that tranny flushed. It's most likely from many mini metal shavings rubbing in the tranny and heating up. Make sure you get that done ASAP, since the A/T Temp light turns on way too late, and the fluid might already be too hot anyways.

I hope I made enough sense, sorry if I didn't.

Marko