Front bearings 99 manufac: 5-99 pretty sure but checking

[gba88]

Hi Guys,
I'm about 99% sure that this is an early 99 composite, but I wanted to double check before getting the bearings.

With the rotors on (can't remove them, it needs to be driven to work in about a half hour), the center piece comes out about 3/8" and the studs measure about 1".

I seem to remember when I switched wheels with another 99 that I thought there was something up because when putting the wheels on, this 99 seemed to have much shorter studs. Does this all point to composite? Thanks for any help!

 

[gba88]

So anyone know if you can tell without pulling the rotors? How about going by the vin number?

 

[x99j]

my 99 was made in may of 1999 and i have cast rotors? i don't know when the cut off was?

 

[gba88]

my 99 was made in may of 1999 and i have cast rotors? i don't know when the cut off was?

Thanks for the reply! A guy I talked to said feel the edges of the rotors or pull the wheel and look... said that if the edges are solid they are cast and if they have the fins down in them they are composite. I don't know though, I haven't seen that info online anywhere. What complicates it further is that the other 99 I pulled the wheels from was 5-99 too! So that theory is out the window (thinking the 2 99's were made at different times).

 

[GrimmJeeper]

it's a shame the rest of the images in this post no longer display, but it shows the difference in the hubs and studs, and gives some information that may help you.

http://www.naxja.org/forum/showpost.php?p=243395817&postcount=3

 

[gba88]

it's a shame the rest of the images in this post no longer display, but it shows the difference in the hubs and studs, and gives some information that may help you.

http://www.naxja.org/forum/showpost.php?p=243395817&postcount=3

Yeah, I was thinking the same thing... found that before posting but like you said the old images weren't loading. What would really help would be knowing how long the studs measure with the rotor on (like if you just pull the wheel and measure from rotor surface to end of stud)...these are like 1", but without knowing which these are I have no point of reference. Oh, and the ring around the center of the hub measured with the rotor on is the 3/8" measurement.

 

[JrTxJ]

visually you can tell the difference looking through the wheels at the rotors. there's a 'moat'/gap around the earlier style compared to the later where the hat part meets the area where the pad contacts.

I can make comparison pictures tomorrow at work of the rotors & hubs if anyone needs me to.

 

[gba88]

visually you can tell the difference looking through the wheels at the rotors. there's a 'moat'/gap around the earlier style compared to the later where the hat part meets the area where the pad contacts.

I can make comparison pictures tomorrow at work of the rotors & hubs if anyone needs me to.

That would help a lot, but might not be necessary if it's obvious. Is the moat gap at the center or outer edge? I think from what you said the center... hopefully it's wide enough to be pretty evident. I might go out and check it out.... I also found a link on another forum that shows a different measurement from the surface to the top of the "hat" here: http://www.jeepforum.com/forum/f11/rotors-cast-v-composite-835898/

 

[gba88]

visually you can tell the difference looking through the wheels at the rotors. there's a 'moat'/gap around the earlier style compared to the later where the hat part meets the area where the pad contacts.

I can make comparison pictures tomorrow at work of the rotors & hubs if anyone needs me to.

Alright, I looked at my 96, and my friend's 99 (the one that needs the bearings). I could not see anything that was starkly different. Both were rusted really well where the surface meets the hat part, and I THINK I could see/feel a VERY SLIGHT dip or "moat" as you called it. I also noted that the outer edges both appeared to be slightly rounded off (although it was tough to say for sure b/c of all the rust on both!).... and both had gaps/fins in the edges.

 

[JrTxJ]

it's at the center as opposed to the outer edge. there will be a small line of rust from where the pads don't touch it but it definitely recesses on the earlier ones and the later are flat with just a touch of the rust.

 

[gba88]

it's at the center as opposed to the outer edge. there will be a small line of rust from where the pads don't touch it but it definitely recesses on the earlier ones and the later are flat with just a touch of the rust.

They definitely seemed the same, but the 5-99 date has me second guessing it. Both were rusted really well, but both seemed to have the dip. Prob gonna have to pull wheel again tomorrow to be sure though and measure surface to top of hat as indicated on that link i posted (cast = 2 1/8" composite 2 1/4"). Thanks a lot for the help with this!

 

[GrimmJeeper]

did you read the text in the link that I posted? with the wheel off it should be obvious which setup you have. one has a rounded edge on the rotor hat, the other is a sharp corner.it also gives overall measurements for rotor height. one is an 1/8" taller than the other.

 

[the_weirdo]

Here's the full thread from Grimm. Should show which is which.
http://www.naxja.org/forum/showthread.php?t=1008852&highlight=composite

 

[gba88]

did you read the text in the link that I posted? with the wheel off it should be obvious which setup you have. one has a rounded edge on the rotor hat, the other is a sharp corner.it also gives overall measurements for rotor height. one is an 1/8" taller than the other.

Yeah, I read that, but didn't realize they meant the hat I thought maybe it meant the outer edge. I couldn't pull the wheel again last night, so I'll check again today after work. Thanks for all the help with this, guys!

EDIT: I'm also going to measure the stud length on my 96 vs the 99, and that will be one more check to see which the 99 is. I'm SURE when I was swapping wheels at one point, I noticed different length studs in the front.

 

[Shorty]

EDIT: I'm also going to measure the stud length on my 96 vs the 99, and that will be one more check to see which the 99 is. I'm SURE when I was swapping wheels at one point, I noticed different length studs in the front.

I'd be leery of using that as a determining factor-- I've seen many replacement hubs with shorter/longer lug studs (in an effort to consolidate two applications into one part number)

I don't know about Jeeps, but many manufacturers use longer studs for alloy wheels (thicker mounting surface) and shorter studs for steelies to allow wheel covers to fit.

 

[gba88]

I'd be leery of using that as a determining factor-- I've seen many replacement hubs with shorter/longer lug studs (in an effort to consolidate two applications into one part number)

I don't know about Jeeps, but many manufacturers use longer studs for alloy wheels (thicker mounting surface) and shorter studs for steelies to allow wheel covers to fit.

ah, ok... yeah good point. I'm just gonna pull the wheel and check the "hat" for the rounded or angled off off edge. Since these are both pretty old (99 & 96) and multiple owners, it's impossible to know what's been done in the past.

 

[GrimmJeeper]

Here's the full thread from Grimm. Should show which is which.
http://www.naxja.org/forum/showthread.php?t=1008852&highlight=composite

Thanks for that, I updated my bookmark to point at that thread :cheers:


This is all the info you need here gba88:

 

[gba88]

Thanks for that, I updated my bookmark to point at that thread :cheers:


This is all the info you need here gba88:



Thanks again, guys! I'll check tonight then post once more with my findings!

 

[gba88]

Ok guys, here are some pics.... I'm going to go with saying they are "cast", but the experts here can confirm from the pics. The only thing I'm questioning is that these seem to have the "moat" that was mentioned by JrTxJ. After reading the text again, I'd say that these edges are angled and not rounded. Please post any confirmations, Thanks a lot

EDIT: I forgot to mention that I measured the exposed lugnut studs (with wheels ON), and the 96's were about a quarter inch shorter than on the 99.

 

[the_weirdo]

Looks like 2-1/8" to me.