Made an annoying 'discovery' the other night.

I am simultaneously tearing down a 3.0 (95) and 3.5 (04 Altima) block, and it came time to pop out the cranks. I went out and bought a top dollar 1/2 inch drive E14 socket, and went to work.

3.0 (top), 3.5 (bottom). This is how it turned out. One engine took 15 minutes, the other took 4 hours. WTF Nissan. And yes, I ruined the girdle.


3.5 (left), 3.0 (right). Upon closer examination. Not only does the head of the 3.5 bolt not accept the socket at a reasonable depth, the grade of steel is so low, the head could not support the level of torque necessary for uninstallation. The head would begin distorting/indenting even with more than adequate socket pressure onto it, and the breaker bar being pulled at 90 degrees. The thickness at the base of the 3.5 bolt would give the impression that it is 'stronger', but my guess is the added material simply compensates for the softness of the metal.



3.0 (top), 3.5 (bottom)



Now my question is: was this cost cutting measure only applicable to Altima 3.5's? Did you guys with Maxima/I35 blocks run into this same problem? I have read that the 02/03 Maxima blocks are E12's, and the 04+ are E14's, can anyone confirm this?

 

Holly ****! I wonder if they are replacement for those bolts, like ARP or the ones for the HR????

 

Looking at the good bolts, the 3.5 seems "slightly" lighter not having that nub at the end of the threads and stronger more matrial on top of the chamfer. If i broke the first one, id hit the rest with a little heat. And those bolt were designed with vertical load in mind not torsional. It sucks, ive been there done that with more hardware then i can count. Chaulk it up as experience for next time.

 

anybody got a 3.0 girdle and 3.0 main bolts on a 3.5 block? Any reason not to?

The 'regular' style E14 I used doesn't 'click' onto the head of the bolt like it does on the 3.0 bolts. A search on here led to a result where a 'snap on' brand e-14 deformed the bolt with minimal torque, I used a 1/2 drive 'unitool' brand e-14 with the same results.

Apparently- if the FSM has representative tool illustrations, there is a Nissan recommended torx socket design.

credit: EM.pdf (from a 2007 book)



Compared to a 'regular' torx design.

 

I had no issue tearing down my 3.5 with generic torx sockets. Maxima engine though...

 

damn, sorry to say but that seems like the wrong tool was used. I havent had issues with 3.5 mains bolts removal.

 

Interesting. No issues here either with my 3.5 teardown.

 

^^hmm thanks. No problems eh. . .

. . .couple open questions before I spend anymore money. The used 3.0 bolts are within standard spec, and the tightening specs are the same for 3.5 or 3.0 bolts, is there any reason not to use them in a 3.5? The whole assembly will be balanced with a lighter fly/pulley.

Are high RPM VQ balancing issues/failures ever attributed to the main bolts?

Assuming beefier rod/head bolts, mid 7K and higher CR, is there any evidence/reason to upgrade main bolts on a naturally aspirated VQ?

 

I have always been told and trusted that the strongest point on the VQ block is the mains. You shoudlnt have any problems with stock main bolts. Stick with 3.5 bolts.

 

I've torn down quite a few VQs (likely in the hundreds), never had a problem with the main bolts, even using no-name e-torx sockets. Interesting that you had such trouble with them.

 

I know next to nothing about the physics of fasteners, but judging by the differences evident in the pics above, is there any reason to believe 3.5 bolts are stronger?

I'm left with the impression the 'new' non-MIJ blocks simply have components made of inferior materials. In this case, the main's head had to get thicker to compensate for being flimsier, while still needing to clear the girdle - I'll need to find a good little scale to see if there's any truth to this though.

Pmohr: If you have access to any 35DE main bolts laying around, could you check the shape of the head on it, like if a torx will actually 'click' down onto it, a pic would be even better. Thanks

 

All my VQ35 hardware is long since gone, only thing I think I've got laying around are some VQ30 main bolts.

 

You can use it with no problem, i rebuild a 2004 3.5 altima engine in a 4.5 max and the owner broke two studs and we use the 3.0 ones with no problem and is running perfect. It is a DD car and no problem with it.

Now, if youre gonna rev much higher like me, then i reccomend to buy the ARP ones because of the 3.5 bottom problems.

 

^ much appreciated info.

DaveB told me the 04 USA engines started getting different part numbers, and altimas often receive some cost-cutting measures, he also said the 3.0 shares plenty of bottom end bolts with the RB series engines - if that means anything. As naive as it may be, I'm just gonna cross my fingers whenever I up my redline : )

 

A bump. My VQ35DE has what looks like an External Torx PLUS socket. Size is around 10mm, no clue what that is in TORX.

I cannot find the socket for sure. The ends of the points are FLAT, not rounded like TORX normally are, they are like a TORX PLUS.

The FSM for the 2004 says it's an E14 TORX, but it doesn't fit. Any help?

 

ended up using a E14 from snap on to do this, worked great

 

I too am snapping the fluted part off my main bolts. Not sure how I will get those bolts out now. It's almost like Nissan wanted this to be a throw away engine. The more I work on this car the less respect I have for Japanize engineers.

 

Look at the I35 VIN and it'll answer your question! Guarantee the 350Z, 370z, G35, G37 don't suffer from subpar vendor supplies from who knows where? Time to invest in another girdle and ARP 4-Bolt main stud kit p/n# 202-5801....($238.55)

 

I know this is an old post, but I wanted to say that on my 05 Altima SER I had the same problem.

When removing the main cap bolts, every other bolt snapped off at the head.

Looks like Nissan used crap bolts on the Altima VQ engines.

For the record, I bought the ARP studs for everything, as I hate torque to yield bolts.

Maybe this will help someone else who thinks they did something wrong. Its a problem with the bolts, not the person removing them.

 

OH MY GOSH this almost made me give up. 06 Max, got hung up on one head bolt, but when I got the mains . . . pop pop pop, the heads of the bolts came off like a bunch of little rolos. With the head shorn off, I couldn't get one of the socket extractors to bite, so had to drill and use the internal extractors. Started breaking those off too . . . if you get to this point, just make SURE you drill far enough so that you can get the extractor in far enough. I think I got impatient with a couple of them and the extractor just wasn't in far enough. Is there a superior alternative to this bolt that won't cost ARP amounts? All I want is to return this thing to stock. I wonder if the RWD vqs would have different (better) main and head bolts that would fit . . .

 

How is this even possible? The TQ spec is low. A grade 6 bolt from the hardware store can handle that. I would think that the engine would break if they were really that cheap.

I haven't experienced this issue on maxima motors, either.

 

I just took my 03 maxima VQ35 apart and i did strip one main bolt but i didnt really have any trouble taking them other then how tight they were.

 

I literally broke the heads off of two main bolts. These Jap cars are extremely cheap shizz...

Like "SpecVQ" I am just trying to bring my 2002 Maxima back to stock specs. Besides ARP, has anyone found main bolts that don't cost an arm and a leg?....

I'll even settle for stock nissan 3.5 Main bolts.

 

UPDATE:

I'll be going with factory Main bolts. I just hope they are better quality than the originals.

Catalog: Genuine Parts
BOLTMAIN BEARING CAP
Part Number: 1229338U00
Price: $4.40
Price for 16: $70.40

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