Transmission lowering?

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Jawzjeep

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If this isn't the right place I'll go post it over in off-road area.

I have a 91 Suburban with a 6 inch lift kit already on it when I bought it. The transmission and transfer case were lowered. The little spacers were moved under the frame to lower the transmission crossmember down. I'm struggling to see why something that has a like eight foot long drive line needs to have the trans lowered. I get it with a short wheel base but on a burb?
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Jawzjeep

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front driveshaft?

Seems that would make it worse in the front to me. Front output tipping up. No shims on front axle either. Hmm.
 

bucket

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Seems that would make it worse in the front to me. Front output tipping up. No shims on front axle either. Hmm.

I like the way you think. Many people don't realize that the output tips up when the trans crossmember is lowered. With that said, it can actually help (slightly) the angle IF it's one of the longer trans/t-case combos.

Those spacers look a bit excessive though. What are they, 1.75-2" maybe? And aluminum? The factory spacers (simply used above or below the mating surface for improved bolt strength) were smaller and steel.
 

Grit dog

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Doesn’t make sense to me either.
 

Jawzjeep

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From everything I've seen they're suppose to be located inside the frame with the crossmember against the frame. So frame sandwiched between crossmember. I understand a longer bolt has a higher clamping force. That seems to be normal.

Im used to transfer case lowering kits and what they're for. Had one on my first lift for my wrangler. Just doesnt seem needed with such a longer rear driveline. Maybe if it was a k5.
 

shiftpro

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Reminds me of the late 70's.
 

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Seems that would make it worse in the front to me. Front output tipping up. No shims on front axle either. Hmm.

yes, it definitely increases the 'take off' angle.

the lowering impact on the shaft is also minimal compared to the rear output.

dunno why some things like that gain traction but like a fashion fad, people get convinced they 'gotta do it'.

:)
 

Jawzjeep

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yes, it definitely increases the 'take off' angle.

the lowering impact on the shaft is also minimal compared to the rear output.

dunno why some things like that gain traction but like a fashion fad, people get convinced they 'gotta do it'.

:)

Im going to put them back in there correct location and see what the joint angle come out to. I can't imagine I need the case lowered. Its only 6" of lift.
 

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When I lifted my K5('89 Jimmy), I installed those aluminum spacers to partially correct the driveline angle. Not sure, but I think they came with the lift springs??? Without them it would howl pretty good. No vibration with them installed. Probably not needed on a LWB or a Burb. I removed them and put the case back in the factory location once I installed a SYE on the 241 case, which shortened it 6-9", as well as a double CV shaft.

The front shaft is a double CV so it wouldn't make a difference unless being driven at high speeds.
 

Jawzjeep

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Bennyt

I figured it came with a kit. I'm looking if anyone with a burb had to run them. To me its bonkers but you never know. I'm going to move em at some point for sure.

Really I'm not worried about the front shafts angle. I think I might just hate the xfer case hanging down so much.

As a side note I get an odd sound coming from near my firewall when I engage reverse. I think it's against the firewall near the distributor and because the transfer case is dropped that part may be rubbing a little. Almost sounds like the bellhousing is making contact. Engine and tranny mounts are good. Encounter anything like that?
 

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It doesn't make sense but I see it on long bed trucks too. If someone was worried abotu the front drive shaft there is a far better alternative. It's called 2 high and unlock the front hubs...
 

Jawzjeep

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It doesn't make sense but I see it on long bed trucks too. If someone was worried abotu the front drive shaft there is a far better alternative. It's called 2 high and unlock the front hubs...

What's funny that's what i was going to say. Im new here and thought it may sound a bit smart ass. Im a little used to another 4x4 site that will eat you up.
 

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