Let me first give you a quick briefing on my Tonka. It's an '04 F150 FX4 Reg. cab, short bed w/ a 6" Fabtech lift.

A shop that just installed my pinion shims told me today that the front/ top part of the driveshaft (meaning the rear drive shaft from what I understand) has an atrocious angle as well and that I will need to have them drop/shim the transfer case to bring that part of the driveshaft back into allignment, also will have to cut out part of the crossmember for clearence. Plus I was informed that "my" rear lift blocks "are not' tapered, say what.

Fabtech nowhere calls out for this to be done, and this is the 1st time that I have heard of this needing to be done. I spoke w/ Fabtech the other day about the pinion angle and my truck confirmed the shallow "V" that they described for the pinion angle before i got the shims.

The shims cost me $180.


Thanks
Chris

 

The Fabtech lift in relation to the front drive shaft has to be modified, the yokes have to be on the same plane and the teeth have to be notched a little bit, because of the steeper angle, and then of course the shaft has to be rebalanced with the changes. Your right to question what the shop is putting out.

 

STX, your reply is the first time I have heard anything about the front drive shaft needing to be modified. I asked that question about a week ago when I was need of some answers about pinion angle but no one ever replied about the front drive shaft.

From my conversation w/ the driveline shop, my understanding was that they were talking about the rear drive shaft, but at the top of it. Sorry that i didn't clarify that in my original post.

Thanks
Chris

I just learned that i can add cv joints for the higher angles, so i'm gonna explore that first I think. Also calling Fabtech Monday and pick'n there brain.

Thanks again.

 

ST sorry about not hitting the other post, must have been asleep.

Here it goes.

Fabtech will let you know about it when you speak with them. When I first looked into getting a lift, I wanted something simple in design and functional. I did not go with the Pro comp because of the front crossmember not being radiused. Plus I have had three Pro comp Chevys and they all were bad at keeping aligned. The Fabtech offered what I wanted. Well when I initially spoke with Fabtech, they did not share the information on the front driveshaft modification. So low and behold when I go set this thing up and the instruction sheet reads front drive shaft modifiication needed, I was in shock . Well I got on the phone with Fabtech and they were very apologetic about not letting me know earlier in the week. But they only refered to modifications on the systems and not the axles, and I had not asked about it. When they stated no modifications were needed they meant to the truck, ie welding and cutting.

So what are you talking about, was the block not tapered for the new angle?
I am not sure what shimming will be needed?

Confused
STX

 

STX, thanks for your input.

I was under the impression it was all bolt on w/ no mods needed. That's why I went ahead and lifted my truck, I thought it only entailed parts swapage, now I'm really start'n to kick myself. I had a shop install mine. I'm also getting w/ the shop tomorrow that did the install for me and ask them why they didn't inform me of this issue as well. Just glad that I have yet to run it 4WD since the install.

The only thing that I had read was that the front DS might need to be replaced if you exper. vibration in 4hi. I found this in their catalog. The note reads 8. May experience driveline vibration in 4WD at high speed. Order FTS92000 CV Front Driveshaft for extended high speed use.

I really don't want to get into modifying the front DS, honestly i'm start'n to loose major faith in business's. I can hold off on runn'n in 4WD until I get the money to just replace the DS, that should be a simple bolt on i hope. I also picked up a link to Tom woods driveshafts yesterday, he specializes in high angle DS's.

Yeah, the shop that just installed my pinion shims on the rear told me that my Fabtech lift blocks are not tapered. Honestly i think he just gave them a visual and didn't put a tape on them. When I spoke w/ fabtech last Wednesday, I asked them if they used different angled lift blocks to correct the pinion angle for the reg cab, scab, and screw and the answer was no, all the same. So I have a feeling that the reg. cab swb kinda gets the shaft when it comes to getting the proper pinion angle, but that's just my pea brain think'n.

At the moment, I'n not sure how the yoke angle at the top of the rear drive shaft is to be corrected, this guy mentioned something like dropping and shimming. Though I might be confused.

Hope I was able to unconfuse ya STX.
Chris

BTW, does the fabtech kit absolutely require no cutting, drilling or welding?

 

Correct no cutting.
It all gets swapped or added on. This is why I went with Fabtech. It is still the kit of choice for most. I spoke with shops all across TX-major cities only. they all recomded the Fabtech including 4 wheel parts in San Antonio, Dallas, Houston and Austin. Well the technicians did.

I have done IFS lifts since 96 and for the longest it was all Pro-Comp because there was nothing else out there. Fabtech has been around for years but there focus had always been on 2 wheel drive desert runners. So there stuff does really work.

About the vibration, I have taken mine out several times and have not had any problems. All I run is 4HI, it is all soft sand down here.

I hear good things about Woods What are you looking at $$$$

 

Well, I got some answers today from Fabtech. Spoke w/ Tony in tech support and asked him about the front drive shaft mod. first. At the moment, I'm not gonna worry about doing it if the shop never did it, he said that the mod is to the cure the vibe on the front DS when run'n 4Hi up at speed. About the fastest I norm. go is 15 or so which isn't that often. Though I think I'm gonna put a CV joint up front shortly and one on the rear DS from the T-case and be done w/ it. He said I should have no probs w/ the angles on either DS, they haven't had one complaint yet. Also waiting on the shop that did the lift to answer my ? if they infact did the front DS mod, they were supposed to call back after they spoke w/ the mech that did the lift w/ a yeah or neah.

As for the lift blocks, Tony said that they are't tapered, contradicts what Fabtech told me last week and the shop that installed the lift.

About $500 or so for a complete CV DS, take a look at his site, alot of different options to go with, way better than the Fabtech, Tony mentioned that they really don't have a retail price but it would around $850 if I remember correctly, guess it depends on make and model.

Again STX, thanks for your help.
Chris

 

You welcome

Keep on trucking