owenwalk

I just put an SR5 Guage cluster in my 87 4Runner. The fuel and oil guages don't work right. Do I need to change sending units? I assume temp and oil pressure work correctly. Anyone done this conversion and know what else needs to be modified?

mikedog

I've done the SR5 gauge cluster swap on my '88 std. cab. You're going to have to buy a new oil-pressure sending unit in order for the dash gauge to work. I got mine from Carquest for around $40. Lord only knows what Toyota wants for one. LOL! The sending units between the base cluster equipped trucks and the SR5 equipped trucks are different. You need the (oil pressure gauge) type sending unit. They'll ask you what type you need when you go to purchase it. It screws in the same way as the original switch and even the original connector fits on it. However, make sure you use some kind of sealant on the threads before you screw it in the block. I highly recommend using ACE/Hardware brand TFE pipe thread compound paste. It's awesome stuff. There was some talk around here that if you have the SR5 cluster connected to the old idiot-light sending unit, you can possibly blow out the oil pressure gauge on the SR5 cluster.

What type of problems are you getting with the fuel gauge? Does it read lower than what's actually in the tank? If so, I have that same problem too.lol! It seems the farther the needle moves away from the middle point (1/2 a tank) in either direction, the more inaccurate the reading becomes. However, it always seems to read less than what's actually in the tank from about the 3/4 line and below. To remedy this, I decided to install a low-fuel light sender in the tank. It's easy to do and mine was already pre-wired from the factory for this. The gauge gives me a rough estimate of how much fuel is left in the tank while the low-fuel light tells me when I'm really low and need to fill it up. After living with it for awhile, you'll get used to knowing how much fuel you have left in the tank even without the low-fuel light. I usually don't let the fuel-level get that low to trigger the light anyway. Just the first couple of times to see if it worked or not.

owenwalk

Thanks for all that. The fuel guage is acually reading high. Very high. I had to use 1/2 the tank before it started to go down. I actually have the doner vehicle so my plan is to either swap out the guage in the cluster or to swap out the sending unit in the tank. Any idea how difficult it is to get the unit out of the tank?. Do I need to drop the tank or is there an access panel?

Erich_870

Oooh oooh, hey I want to do that! My first gen is a stock SR5 and I have the same problem with my fuel guage. I guess its just how they calibrated them back then . I can go ~120miles on the freeway before it drops to 3/4 full, then its drops at light speed from there. Got any more info on the low fuel level light? I would love to put one in just as a back up. I plan to continue to inhance my rig so I can go on "expeditions" for several days straight like BahaTaco and it would just make me feel better to have another sensor
Was all the wireing there at the tank? Did you have to open the dash up and put in an indicator light?

Erich

foxtrapper

Erich,
I think your rig should have the light stock on the dash, and the three wire sending unit in the tank. You might simply have a blown bulb, or have never gotten the tank low enough on fuel to trip the light. I know my stock SR5 truck has this light and it works when the tank is down to about 2 gallons or so.

If you feel up to playing with you sending unit, you can normally do two modifications to them. One is to realign the contact strip so that full reads full, and empty reads empty. That's just a straight forward moving of the unit. You can also sometimes carefully move the wires on the wrap itself to change the curve profile. I've done it on some, but not a Toyota. Do understand that in the process of shoving that little wire around, you may break it.

Erich_870

I know I have had it low enough that it should have come on, I guess its either the bulb or I don't have one. Where do the sensors wires come out of the tank? I think I will first crawl under and see if I can find them. Then I might open my guages up and check the bulb.

I don't think I'll go that far, I'm pretty sure I'll screw it up and then I'll have no way of telling how much is really in my tank.

Anyone know the specifics on the sending wires? Color, location...

Thanks Guys,

Erich

owenwalk

So yesterday I switched out my base model sensor with the SR5 sensor. It is located behind the fuel pump assembly which is below the access panel under the rear right seat. Of course, you can't access the sensor from that panel, you have to disconnect the filler, overflow, and all pump and fuel line hoses, drop the tank skid plate, them drop the tank about 6" and slide it foreward to where you can access it from the panel. It is not too big a job. But here's the thing. With the SR5 sensor in place, now the guage on my SR5 cluster reads LOW. I don't get it.
Steve

mikedog

Yeah, It seems Toyota was thoughtful enough to prewire all these trucks with the 3-wire gas tank sender harness. If you have the low fuel-light sender with the SR5 cluster, the light should work. My PU was about as "stripped" as you can get back in '88. No A/C, no radio, no wheel caps, no tinted windshield, no double-walled cargo bad, no nothing, but it WAS pre-wired for the low fuel-light gas tank sender. Yipee! That reminds me, Toyota even had the nerve to charge you extra for "metallic" paint back then.

I didn't have to open up the dash. The light was already installed. They just snap-in from the back. However, it's always a good idea to check out all the bulbs to make sure they light properly though. When I "loosely" installed my SR5 cluster to check out all the bulbs, some of them weren't as bright as some of the others. I had to mix and match a few bulbs from my old cluster to get the evenly matched back-lighting that I wanted.



-mikedog

dajabr

I did a write up on customizing lights in the 1st gen SR5 gauge swap, combined with having to adjust milage, then swap the odo again due to really loud noise in winter I've had to take this gauge console apart a million times, and would love to save somebody some trouble...

http://va4roc.com/archive.htm