4.0 Idler Pulley Replacement OEM vs Gates Reference

That’s incredible.

 

Bumping this back up vs starting a new thread. I attempted to change my idler pullies this past weekend, no dice. The bolts are so rusted, I started to round them off. I was going to grab one of my "biter" sockets, when I realized i probably should not do that since I do not have new bolts, washers etc... I bought a koyo kit offline, cant recall where. Its probably fake now that i read through this thread, but it is what it is now. Does anyone sell aftermarket bolts and washers that are the correct fit for this truck, or would i be better off just going oem?

Also, when i took the belt off i found out the tensioner pulley is bad as well. Is buying the gates tensioner and swapping out the pulley still the best option? thanks!

 

If you feel that the tensioner is putting plenty of tension onto the serpentine belt, then replacing just the bearing is pretty easy.

Unfortunate about the bolts. Even though my taco spent several years in places with salted roads, I had no trouble getting mine out. Made the replacement job super easy. I’d go OEM myself but I know that if I had needed to replace one, I would’ve headed over to the hardware store and picked up a replacement there.

 

The pulley on the tensioner is pretty trashed, all of the pullies are pitted and rusted so i'm going to just replace all of the pullies with new assemblies rather than swap out the bearings.

i'm worried if i can get the bolt out, that the hardware store might not have an exact match. I think i'll just order new oem ones to be safe.

 

This is the no-brainer to me.

 

Many just replace the tensioner pulley but I did the whole assembly as had belt slip at full throttle and downshifts so tensioner was getting weak.
Full tensioner assembly requires dismounting the alternator and AC compressor as its the base they bolt to/thru. A pain in the ass.
Need to soak the bolts in PB Blaster or other penetrating oil and always use a good quality 6 sided socket (not 12pt)!
Bolts are specific length so good luck mayby a good ACE has a match but note that the #1 post has the bolt part #s so save yourself the hassle and get OEM.
Good luck and wear gloves and save your hands. Might help having a second person holding the socket on from above as you work from the bottom.

 

Oh yeah, i soaked this with blaster for 2 days. I attempted my standard 6 point socket and they just won't grip. Heck, the one won't even fit on the bolt its so rusted. And there isnt a ton of room to swing a hammer. i order the new bolts and washers and such, give it another shot (hopefully before winter hits) and if i cant get i'll just have to take the truck somewhere and have them do it.

 

Well, i'm still working on this project. A couple of items are on back order from Toyota...

 

So were you able get those rusted bolts out?

 

Havent given it my second attempt yet. I wanted to wait until i had the new hardware since i dont plan on re-using the junk thats on there now. But, with how cold its getting to be, i might end up taking the truck somewhere and pay them to swap them out.

 

how did you get to the bottom two air conditioning compressor bolts to remove them to move the AC out of place to get to the tensioner?

 

It's been awhile but I don't remember them being super hard to get to.

 

Bumpin' the thread. I see according to google images, there are two Idler number 2's... The left most as well as the upper most idlers. Then there is the right bottom most idler. I see that the oem part numbers are 16603 and 16604. Would anyone have any technical manual/data that states which part number goes with which idler? Really scratching my head here trying it figure out.

To the best of my knowledge and research it seems like I need two 16603 pulleys and one 16604 pulley.

 

Did you look at the diagram on the first post?

 

I did, just confused by it

 

If you're just replacing the idlers you will need two Number 2 Idlers (16604-0P011) and one Number 1 Idler (16603-0P030)

 

My hero!! Thank you so much that’s all I needed!

 

Alternatively, if your pulleys are in good shape, you can replace just the bearings. 6302RMX (bearing size:10x42x13) is the part #; you need four bearings because the #1 idler is a double bearing. Also consider replacing the bearing in the tensioner pulley, type 5203-2NS, size: 17X40X17.5 (other types: 5203-2NSL, 5203-2RS; or Febest pulley/bearing #

$44 0187-GRJ200 OEM 16620-31012

0187-GRJ200). Rodavictoriausa is a good source for the bearings.

 

This is what I did for pulleys I pulled off that way I have spares.

 

Has anyone on here replaced the OE #1 idler with the

$42 gates 36174 idler pulley

gates 36174 idler and also have the supercharger kit? Did you have any issues with alignment on the supercharger Idler that sits on top of this pulley ?

I tried replacing this #1 OE idler today only to find out that the 36174 gates pulley isn’t as wide at the bearing like the OE double idler and throws off the spacing for the lower supercharger idler pulley that sits on top of it. Pics below for ref :

Pulleys side by side

OE pulley spacing with supercharger idler

gates pulley spacing with supercharger idler