GM 14 bolt semi-float 9.5 Mag-Hytec cover

[cdm1993]

I am installing the Mag-Hytec rear differential cover for the GM 14 bolt 9.5in, but the bolts are bottoming out and not allowing me to tighten the cover. Has anybody experienced this problem before? (The old cover bolts will not substitute)

The previous cover was sealed by black RTV, and a lot of it got into the female threads. I have picked at them with screwdrivers, sprayed with acetone, and am now currently tapping the threads, but the new bolts are still not clearing. The threads are as clean as I can get them. Can I shorten the bolts somehow? I was thinking about buying new bolts.

Thanks

 

[bdcardinal]

What is the difference in combined thickness of the cover and bolts Mag-Hytec compared to OEM?

You should always use a thread chaser on any hole with RTV guts in it.

 

[cdm1993]

The new bolts seem to be at least 3 mm too long.

 

[oldhp]

Use shorter bolts or cut the ones have.

 

[UNC151]

I would contact Mag-Hytec before doing anything drastic. I have had 3 different covers (all Ford) and never had any issues. I did need a new o-ring and contacted them and they sent one out at no charge. I am sure that customer service would help you out--they stand behind their products.

 

[cdm1993]

Thanks all I appreciate the help.

 

[bvance554]

Buy shorter bolts. Thats not drastic.

 

[UNC151]

Originally Posted By: bvance554
Buy shorter bolts. Thats not drastic.
Why? He already paid for the bolts--which are stainless allen head and may not be that easy to find. I would ask Mag-Hytec to provide them. There may also be something wrong with the cover--a phone call would not cost anything and would allow the vendor to "make this right".

 

[bdcardinal]

While I would normally just go to Fastenal or ARP, in this case the OP paid for something that should have worked out of hte box. I would totally give Mag-Hytec a call and explain everything. Maybe take some pics for them. It could have very well been an error on their part in the boxing process.

 

[cdm1993]

I did just that and went to Fastenal and got some 8mm that were slightly shorter than the boxed 30mm. I think the new ones are 25mm. Fit much better.

I agree I should have probably called, but I needed to get this project done, and I busted a couple of the Mag-Hytec supplied bolts, so it was on me. The thread pitch is 1.25mm for anyone who ends up in the same situation as me.

The cover is fantastic. Excellent build quality, looks nice, feels solid, will make future rear diff fluid changes a breeze, holds 3 (for the 9.5) extra quarts, has cooling fins (more fluid and cooler fluid is bueno), and it is made in the U.S.A. I would highly recommend it.

 

[bdcardinal]

I would still let them know so they can correct it in the future.

 

[Jeff_in_VABch]

Hopefully you used the washers.

 

[bdcardinal]

Originally Posted By: Jeff_in_VABch
Hopefully you used the washers.


I hope he did and remembered the first go around. I would say a washer is right around 3mm or so thick. I tend to assume anyone switching out to a cover like the OP got would not have to be reminded to use washers, regardless of what Carrol Smith said about them.