Need help setting pinion angle...

[dSINtia]

Hi guys.

I recently wrapped up a V8 conversion in my 2WD B2 and although the stock 7.5" rear end seemed to handle the torque of the V8 well, I opted to swap in an Explorer 8.8" axle with LS 3:73 gears and disc brakes.

After stripping the B2 of stock parts and preserving the underside of the vehicle and rebuilding, preserving and painting the 8.8" axle I 'THOUGHT' I was ready to weld the new RuffStuff spring perches in and get the axle mounted.

I put the vehicle at ride height with the suspension loaded, took my measurements and tacked it all in place. I am 3.0 degrees down (87 degrees) at the transmission and exactly at 90 degrees (or 0 degrees if you prefer that perspective) at the pinion giving me -3 degrees to allow for axle wrap as I'm still at stock ride height with stock leaf springs. I do have air bags installed just forward of the spring plates though.

Anyhow, I weld everything up, retake my measurements and all my angles are the same leaving me down 3 degrees at the pinion from parallel with a 15 degree drive shaft angle. The drive shaft and u-joints are new with a slip yoke at the trans and the 8.8 flange at the pinion end.

I have horrible vibration/knocking even at idle speed - I haven't even dared take it over 10 or 15 MPH.

What have I done wrong? Did I give it too much negative pinion angle over-compensating for less than expected axle wrap? What should I do to correct it? Shims? In front of or behind the axle?

I thought I understood all this pinion angle stuff but apparently I'm not quite as savvy as I thought... any help is greatly appreciated!

Thanks.

Dave

 

[alwaysFlOoReD]

This may help;
http://www.therangerstation.com/forums/attachment.php?attachmentid=12939&d=1389987591

 

[dSINtia]

Thanks Floored... I've read this bulletin before. Assuming you can make sense of the advanced alegra in there, there is some good stuff but not much to help with my current situation.

I'm thinking about ordering some 3 degree shims and raising my pinion to 93 degrees to mirror the angle at the trans (87). Angles will equal exactly 180 when static and If I get axle wrap under hard acceleration I will likely get some vibes but not during daily driving.

 

[alwaysFlOoReD]

Was the 8.8 known good? Perhaps the gears or bearings are fubar? I also seem to remember that the b-2 axle is not centered like the rangers. I put an 87 stx ranger axle in my b-2 and made adapters for the perches. The new axle was offset. I never did anything about it tho and never had any harsh vibration.

Richard

 

[dSINtia]

Excellent question Richard. The answer is no... It isn't a known good axle but all checks out and the diff was very clean and damage free upon inspection. The Expo axle is offset by about 2 inches but I seriously doubt that will affect it much even though the B2 stocker was centerline. I can't find 3degree shims in stock any where around here but I did find some 2 degree shims I'm picking in tomorrow morning. I will try that first and see what happens.

 

[dSINtia]

2 degree shims did the trick... Driveline vibes are gone but now that I have a smooth driveline I can tell I have a passenger side wheel bearing that is in dire need of replacement.

 

[alwaysFlOoReD]

[emoji106]

sent while sitting on the throne

 

[dSINtia]

Grrrrrr. Got the pinion angle corrected using to 2 degree shims only to reveal a thrashed ring gear... I think. Maybe pinion gear or carrier bearings as well. I got crazy loud whining and whirring under throttle and howling at speeds over 15 mph. Anyhow, I'm looking for a set of 3.73's.

Question is, is it worth buying the specialty tools and doing it myself or should I just cough up the cash and pay someone to do it for me providing them the gear set?

 

[PlumCrazy]

If you plan on regearing later its a wise investment to buy the stuff and do it yourself. It wont save you much up front...but next go round will be cheap if you already have everything. The only thing you really need aside from the install kit and basic tools is a dial indicator and maybe a set of calipers for measuring shims. Unless you have a shop press...removing/installing bearings will cost you a few bucks to have done.

For setting pinion depth I recommend buying a Ratech setting tool, they are under $40 and save you a good bit of time.

 

[chvlfrk]

Grrrrrr. Got the pinion angle corrected using to 2 degree shims only to reveal a thrashed ring gear... I think. Maybe pinion gear or carrier bearings as well. I got crazy loud whining and whirring under throttle and howling at speeds over 15 mph. Anyhow, I'm looking for a set of 3.73's.
Question is, is it worth buying the specialty tools and doing it myself or should I just cough up the cash and pay someone to do it for me providing them the gear set?

=====================
PM sent

 

[win]

The 8.8 is pretty darn easy to work on and for a fresh set of bearings, all you'd really need is a 20 lbs/in torque wrench (yea, pretty small)

http://www.angelfire.com/theforce/5ohcpa/cpa5ohtech001.htm

Reuse the original shims and all you've got to do is set the initial preload on the pinion bearings.

 

[bobbywalter]

mirror the t case and pinion....down maybe 1 deg max on pinion.

the left right offset on the explorer/ranger/b2 pumpkins is a non issue in the b2. there can be issues using a b2 axle in a ranger though with driveshaft rub depending on situation.


if using factory gear ratios anyway, i just go get another axle from the yard when i murder one....the 8.8 is too weak for me, but the explorers do put up a good fight. finding a decent condition rear axle is way cheaper then fixing one where i shop. where you are at it may not be the case....here its 50-150 bux for one.