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Bob98SR5
03-28-2007, 09:44 PM
TJM 17 Front Bumper Installation
By: Bob_98SR5
Written: 12/20/05
Vehicle: 1998 4Runner

Parts
TJM 17 front bumper
Sonoran Steel Modified TJM Bracket/Shackle Hangers (Optional)
Cruiser Accessories black license plate holder #79150- (Optional from Kragen)

Tools & Supplies
Socket wrench set (metric or SAE up to 19mm)
Combination wrench set (metric or SAE up to 19mm)
Socket wrench extensions (various sizes)
Rustoleum Flat Black paint
Wire stripper
Soldering gun/solder
Electrical tape
Heat shrink tubing
Zip ties
Utility blade
Scissors
Drill with drill bits (optional for Hella lights)
Combination square (for measuring light holes)
Sharpie pen (optional for license plate)
1 1/4" bolts with washer and nuts (optional for license plate)

Summary
This upgrade is very easy and doesn't require an extensive writeup, but there were a lot of "little things" that people might not get the first time, so that is why I'm documenting this in a writeup. Also, there are a bazillion threads on the net and on many off-road forums about installing TJM front bumpers, so I've culled the valuable tips into this writeup. Hopefully, this will become the definitive writeup on TJM bumper installs :)

Why upgrade to a TJM 17 front bumper? Several reasons that I can think of: a) better approach angle b) beefier bumper c) better appearance and d) a platform for a cb antenna, hi-lift and/or driving lights. Regarding the question, "How much does it weigh vs the stock bumper?", the TJM pieces including the nuts weighs 70.0lbs. My 1998 stock bumper and brackets weight 21lbs---a huge 50lb difference. I'm sure this is number will be a source of dispute, so I'll describe my weighing methodology: I used a digital scale, weighed myself, and then one by one, weighed me holding each part and subtracted the part weight from my body weight.

As I'm sure this question will come up too: I purchased my TJM from Steve Schaefer of Sonoran Steel (Tempe, AZ). I also bought his used, modified bracket/shackle hanger from him as well. Of note, I went in together with two other guys, had the bumpers shipped to a commercial address, and got a reduced rate on the shipping. This is about the only way you can save a few bucks on these bumpers. He was really great with customer service and his prices were very competitive.

And on a side note: as the number of off-road fabricators seems to dwindle in number every year, keep this in mind: when they are gone, they are gone. So do your best to "Support your local off-road specialists."


Step 1: Removing the Stock Front Bumper
There are a total of 10 bolts you need to remove and two harnesses that you need to cut in order to remove the front bumper. Begin by removing the front tow hook and tie down with a 18mm socket. Keep these four bolts as you will reuse them. Next, unbolt the two 14mm bolts from each bracket (total of 4). You will not reuse these bolts.

http://4runners.org/image/t17/t17_09b_towhook_on.jpg
Remove 18mm bolts (B)

http://4runners.org/image/t17/t17_02_mainbolts.jpg
Remove 14mm bolts (B). Notice rust (R). Rustoleum later

Locate the two smaller bolts at the ends of each bumper and remove them with an extended 10mm socket. Note that there are two bolts that you can remove, but the bottom bolt is much easier to access. Next, clip each turn signal harness wire about 2 to 3" from the grey harness plug. After removing these last two bolts and clipping the harness, give the bumper a good downward tug and the bumper will come off.

http://4runners.org/image/t17/t17_01_littlebolts.jpg
Removing either nut #1 or #2 will cause the bumper to come off. I chose #1

http://4runners.org/image/t17/t17_04_turnsig_snip.jpg
Cut harness wire (C) and then remove black wire cover

Next, remove the two bolts inside the crash absorbing mounts by taking an extended 12mm socket to it. Give it an upwards whack to remove these ends. Place both aside with bolts, especially if you intend to sell or remount the front bumper at a later date. After removing all the hardware, now is a good time to give all the rust-affected areas a little hit of some Rustoleum Flat Black paint or POR15

http://4runners.org/image/t17/t17_06b_nubs.jpg
Unbolt recessed bolt (B) with extended 12mm socket

http://4runners.org/image/t17/t17_02b_bare_mount_area.jpg
Hit all rusted areas like area (S)



Step 2: Mounting the Brackets
Remount the tow hook and tie down onto the new TJM bumper brackets and into the threaded bolt holes inside the chassis rail with the four 18mm bolts (2 each side). Hand tighten them; do not tighten them down. Next, loosely tighten down the front of the bumper bracket onto the chassis rail end using the TJM-supplied M8 x 1.25 x 20 bolts with a lock washer and a 25mm flat washer.

Because I used the Sonoran Steel modified brackets, I did not reinstall the tow hook and tie downs. As you can see, Steve welded in a shackle hanger mount on the ends of each bracket. And as you can also see, I bought Steve's "previously used" brackets! They are still rock solid, so no worries there.

http://4runners.org/image/t17/t17_07_schaef_vs_stockbrkt.jpg
Stock bracket on the left vs Sonoran Steel bracket w/ shackle hanger (S)

http://4runners.org/image/t17/t17_11_bracket_bolt.jpg
Remounted brackets with existing 18mm bolts (E) and new bolt/washer (N)


Step 3: Assembling the Bumper
The bumper comes in three pieces: the main center section and two wings. Also, there are two rubber gaskets that go in between the ends of the center sections and the wings. Test fit the gaskets and make a cut where the gasket where the top of the wing ends (I forgot to do this). Then for each side, hand tighten the supplied 5/16" x 1" bolts, two washers and a lock washer. Work on one side at a time. If you have someone around, have the person pull really hard on the gasket so that you do not leave any gaps between the gasket and the bumper pieces while you tighten it down. One tip is to have the nut side facing the rear and use a combo wrench to hold down the bolt head while you crank down.

It's important that you do this to your satisfaction NOW. I got it about 90% flush by myself, but its not a huge deal to have a small gap. Later, I tried adjusting it with the bumper on and it is very, very difficult because of the lack of hand space.

http://4runners.org/image/t17/t17_11_wing_wrenchd.jpg
Face nuts (N) towards inside of bumper. Pull on gasket while tightening down to avoid gaps

http://4runners.org/image/t17/t17_12_trim_gap.jpg
Slight gap (G)


Step 4: Wiring the Turn Signals
Remove the stock black plastic covering and then strip down the 22AWG stock green/black and white/black wires.* Then strip down the black/red and black 18AWG TJM wires. Twist each wire tight and then twist them together onto each other. Next, put a piece of heat shrink tubing onto the wires (either side). Next, tin your soldering iron and then touch the soldering tip to the underside of the twisted wires. Allow the wires to get hot and touch the solder to the wires. Allow the solder to flow through the wires. Repeat for all 4 wires. Next, wrap each connection with a little electrical tape and then heat shrink the tubing to make it weather resistant.


WIRING
OEM Green/Black (+) to TJM Black/Red
OEM White/Black (-) to TJM Black

http://4runners.org/image/t17/t17_13_heatshrink.jpg
Harness (H) which has been soldered, electrical taped and heat shrinked

*Your stock wires might be different colors, so please refer to your vehicle's wiring chart colors.


Step 5: Mounting and Adjusting the Bumper
This is part of the writeup deals mainly with the problem that most, if not all, people experienced: an unlevel bumper. If you do not push upwards on the wing ends of the bumper while tightening down, you get a bumper that points downwards at the wings. It looks really odd. Of note, you should have about a 1/2" of space between the bumper and the bottom portion of the quarter panel. Here are some shots of an unleveled bumper vs a leveled one:

http://4runners.org/image/t17/t17_16b_adjust_wings.jpg
Unleveled bumper with gap (G) is not desirable

http://4runners.org/image/t17/t17_11_level_left_3.jpg
A leveled bumper with no gap (N) is what you want

Begin by mounting the bumper onto the brackets. The bumper's mounting plates on the inside of the bumper itself should fit *inside* the mounted brackets. If you cannot fit them in, untighten the bracket's bolts a little until you can squeeze the bumper plates onto the brackets. You are now ready to tighten down the lower two 18mm bracket bolts and the front M8 x 1.25 x 20 bolts.

Next, hand tighten the 2 sets of four 1/2" x 1/2" bolts. Use washers on each side and use a lock washer as well. As with the bumper wing bolts/nuts, have the nut side facing the center of the bumper. If you are doing this solo like I did, lay on your back parallel to the bumper and use your foot to push up the wing end and tighten down the bolts---a little acrobatic, but doable. Of course, you can skip the acrobatics and call a friend over and help you get the bumper level while you tighten down. :)

Lastly, make sure you wrap and tuck the excess driving light wires out of the way. I secured the wire bundle with one zip tie and then used another to hang that bundle up with a second zip tie.

http://4runners.org/image/t17/t17_13_main_bumper_bolts.jpg
Nuts (N) should be faced inwards towards the center

http://4runners.org/image/t17/t17_14_ziptied.jpg
Zip tie (1) secures wire bundle. Zip tie (2) hangs bundle out of the way

Of note, 00Runner has some good advice here as well: tighten the bolt that is highest and closest to the front of the bumper while leaving the others loose. This will allow you to pivot the bumper upwards at the wing ends. Then tighten down the bolt that is lowest and closest to the engine. This will allow the bumper to be secured enough to allow you to tighten down the other bolts.


Step 6: Finishing Touches (Optional)
Regardless of any mod or upgrade that I do, it must not look too far from stock. Pretty difficult considering this bumper is like the devil spawn as compared to the stock bumper, but nevertheless, I did a few things here to make it look as stock as possible.

Since I currently do not have a winch and wanted to comply with California license plate laws, I went to my local Kragen and purchased a license plate holder. The holes on the license plate have no comparable mounting holes on the TJM bumper and the last thing I wanted to do was to drill into it. So I purchased a generic plate holder, drew the location of the four TJM winch mount holes onto the plate holder by holding it onto the bumper and then drawing the holes from the back with a Sharpie pen. Next, I used a 3/8" drill bit and drilled holes through the license plate and the plate holder in the marked locatoins. I secured the plate holder and license plate down with some left over Toyota bolts/nuts I had from a previous project. It looks industrial, but Mikey likes it :)

http://4runners.org/image/t17/t17_19_plate_drill_hole.jpg
Drill plate and plate holder at points (N) by tracing plate holder against stock holes in TJM bumper

http://4runners.org/image/t17/t17_19_plate_bolt.jpg
Industrial looking, but I like it :)

Also, I removed the smaller, rearward bumper hangers, trimmed some of the plastic off and painted it flat black.

http://4runners.org/image/t17/t17_13_wires_misc_piece.jpg
Trim along line (T), remove part (R), and spray paint this part (P)

http://4runners.org/image/t17/t17_14a_remd_paintd.jpg
Spray painted

I also took the Rustoleum Flat black to alot of the exposed parts that I missed including the radiator support, the skid plate, and Steve's shackle hangers. I also notched out two holes in the winch control box cover with a utility knife to accomodate the Hella driving light wires. At this point too, you can put the shackles onto the shackle hanger points and secure them with zip ties.

http://4runners.org/image/t17/t17_18_fine_spray_brkt.jpg
I spray painted the bracket, skid plate, etc

http://4runners.org/image/t17/t17_10_hole_cover.jpg
Cut notches (N) for the driving light wiring

Finally, I remounted my Hella driving lights by using a drill and successively larger drill bits until the stock mounting bolts could be dropped through. I think the right one is off by a 3/8th of an inch (arrgh). Anyways, if you're interested in that writeup, go here.

And here is a pic of the mounted TJM bumper on my 4Runner. Oh yeah, those cheap TJM aluminium-backed stickers had to go. They weren't even put on straight! I did relocate one to my wind fairing, but i think that will fall off soon.