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View Full Version : from 4.11's to 4.88's


jjhancock
11-13-2009, 12:31 PM
Hey all, need some guidance here.

A little background info... 80 series with 130k. Front and rear axle rebuilt by a pro slightly less than two years ago and no problems, no strange noises, no gear whining, nada. As far as I know everything is normal. This was about 20k miles ago. Everything is smooth as silk at this point.

So I've been rolling 285's and recently got the opportunity to upgrade to 4.88's as a friend wanted to go back to 4.11's from 4.88's after a diesel conversion. He has never had any problems with the gears, and I rode in the truck before we did the swap and all was well.

So we had the swap done by a pro toyota tech (not the same as who did my front axle service), and according to him all went well. I picked up my truck last night, and I now have what I describe as a gear whine now with the 4.88 3rd's. Is it normal to notice a gear whine, that's intermittent, and completely reproducible by getting up to a speed of say 55 mph, letting entirely off the gas, and then giving a teeny tiny bit of gas to hear the whine? (happens at 35mph and other speeds as well) I really think something isn't right with my front axle now, but I might also just be paranoid. I ended up driving it back to the shop and catching a ride home since I didn't want to do any damage if something wasn't right.

So, I guess my first question is... should a front axle that was silent in terms of gear whine with the stock gears now be noisy, intermittently, with 4.88 gears?

We checked the gear oil and the diff is full. If this is normal, I don't think I can live with my DD making this kind of noise. I know several of you have 4.88's and 315's, and that's where I'm at right now... The truck feels like it's geared close to stock with the tire + gear combo, but I can't live with the whine. I'm seriously hoping I don't have to go back to stock gears and 285's.

Thanks in advance to everyone!

-Justin

Uncle Ben
11-13-2009, 12:49 PM
Did you just swap thirds or did the gears get re-set up? If it's the later, drive it for a bit and see how the gears re-seat. Check the diff temps with you hand also as used gears set up too tight will often get really hot!

jjhancock
11-13-2009, 12:56 PM
We swapped 3rds and according to the guy who did the swap, the gears were in awesome shape. I'm at a loss at this point...

nakman
11-13-2009, 01:42 PM
One thing you could do with a CDL switch is drop one or the other driveshaft and just isolate if it's front or back. But sounds like it's in the front if was so bad you didn't want to drive, does the whine sound like it's coming from the PS front tire?

Another thing may be to swap gear oil to something thicker.. or to dyno if you're running synth. Just to see if the tone of the whine changes to something livable, but it probably won't make it go away completely. That's a bummer man, sorry. :(

jjhancock
11-13-2009, 01:45 PM
One thing you could do with a CDL switch is drop one or the other driveshaft and just isolate if it's front or back. But sounds like it's in the front if was so bad you didn't want to drive, does the whine sound like it's coming from the PS front tire?

Another thing may be to swap gear oil to something thicker.. or to dyno if you're running synth. Just to see if the tone of the whine changes to something livable, but it probably won't make it go away completely. That's a bummer man, sorry. :(

I'm 99% sure it's coming from the front. I do have a CDL switch, and I am considering dropping one driveshaft at a time to see if I can isolate it. The truck is still at the shop so I'm hoping they figure out what the deal is and can fix it. A professional with listening tools and a rack has a way better chance of figuring this out than I do. I'm confident I'll get it figured out, I just hope it's soon as I don't really like driving my 40 in the snow a whole lot.

I'm pretty sure the diff is full of dyno since I didn't request synth, but that's a good call to switch to something thicker. Also, considering the fact that more has to come apart in the front axle than the rear to swap the 3rd, there's a chance that there's something else wrong in the axle and that the 3rd is completely fine too.

wesintl
11-13-2009, 01:45 PM
buy swampers :D

Uncle Ben
11-13-2009, 01:45 PM
One thing you could do with a CDL switch is drop one or the other driveshaft and just isolate if it's front or back. But sounds like it's in the front if was so bad you didn't want to drive, does the whine sound like it's coming from the PS front tire?

Another thing may be to swap gear oil to something thicker.. or to dyno if you're running synth. Just to see if the tone of the whine changes to something livable, but it probably won't make it go away completely. That's a bummer man, sorry. :(

Werd! :thumb: Also, do you know what brand of gears they are? If they are Yukon or Precision I would isolate which one is talking and have a closer look at it.

Bobzooki
11-13-2009, 01:47 PM
Go figure - jjhancock is sitting RIGHT NEXT TO ME in a Crystal Reports class. What're the odds of that? I see him pop up Rising Sun, and say "huh?"

jjhancock
11-13-2009, 02:35 PM
Werd! :thumb: Also, do you know what brand of gears they are? If they are Yukon or Precision I would isolate which one is talking and have a closer look at it.

The gears are Precision brand and they were set up with Toyota factory install kits.

AxleIke
11-13-2009, 03:38 PM
I'm going to be watching this one CLOSELY. I have this EXACT problem!

jjhancock
11-13-2009, 06:26 PM
AxleIke -

How long have you been driving your rig with this issue going on? Considering this weather, and the fact that I just drove my 40 with the bikini top on from Denver to Boulder, in the snow and rain, I'm really anxious to get back behind the wheel of my 80... The reason I left it at the shop is that I didn't want to do permanent damage to anything. The techs as well as my buddy both didn't think there was anything wrong, so maybe I'm safe to drive it until I figure this out? I would just hate to destroy the ring and pinion or an inner axle, etc and making things worse.

AxleIke
11-13-2009, 09:01 PM
AxleIke -

How long have you been driving your rig with this issue going on? Considering this weather, and the fact that I just drove my 40 with the bikini top on from Denver to Boulder, in the snow and rain, I'm really anxious to get back behind the wheel of my 80... The reason I left it at the shop is that I didn't want to do permanent damage to anything. The techs as well as my buddy both didn't think there was anything wrong, so maybe I'm safe to drive it until I figure this out? I would just hate to destroy the ring and pinion or an inner axle, etc and making things worse.

I've been driving like this for months. No change in the noise. I keep hoping it might get louder or quieter, but its just stayed the same.

I have to get above 40 mph or so, and then, just like you, a very light push on the accelerator will give a whining/howling noise.

I can't stand it, but I don't know what to fix???

jjhancock
11-14-2009, 08:57 AM
Sounds to me like I'm safe to drive the truck anyway. Thanks for the info. As far as the noise goes, I'd be interested to take a ride in your 80 to hear first hand what the sound is like in your drive train. That may be easy to arrange since we're both in Boulder. I'm thinking the garden hose technique while driving down the road listening to the tranny / tcase / diffs is going to be in my near future.

Red_Chili
11-14-2009, 08:57 AM
JJ-
Re-check the basics, beginning with driveshaft phase. Very easy to get off one spline and not notice, if the driveshaft separated during the work (like that happens... :lmao:).

Assume nothing, look at everything. Pinion preload comes to mind too. Backlash. That sort of thing.

Sound can carry through the whole drivetrain so isolating it is key.

JadeRunner
11-14-2009, 12:47 PM
I just had Robbie setup Nitro 4.56's for me. I would get intermittent wines like that at various highway speeds. But, it has all gone away as the normal break in period as elapsed.

AxleIke
11-14-2009, 02:00 PM
Nah, I don't think its a a set up thing, as mines been steady and unchanging for hundreds of miles now, and 2 oil changes.

I went down and looked at my driveshafts.

Both are 90deg out of phase, but that seems to be the norm for double cardans, right?

The rear *might* be off by one spline, but I doubt it. I'm going to pull it tomorrow to be sure.

nakman
11-14-2009, 02:27 PM
JJ-
Re-check the basics, beginning with driveshaft phase. Very easy to get off one spline and not notice, if the driveshaft separated during the work (like that happens... :lmao:).

Assume nothing, look at everything. Pinion preload comes to mind too. Backlash. That sort of thing.

Sound can carry through the whole drivetrain so isolating it is key.

That's a really good suggestion was the driveshaft apart? Remember the front driveshaft is 90 degrees from the rear- so if the pinion flange alignment looks the same on both then there's your problem.

jjhancock
11-14-2009, 03:44 PM
Chili - I talked to the guy who did swapped the 3rds in for me and he said the drive shafts didn't come apart. He had the truck up on a lift and I think just wired them up and out of the way at the pinion end. That doesn't mean that my probably original u-joints didn't get jarred in a direction that has made one of them start to make noise. I have some brand new toyota u-joints in the box and I'm going to go ahead and pop them in and have them re-balanced anyway, just as good measure. I never heard this noise ever before, so if the drive shafts didn't come apart, I kinda doubt that they are the culprit, but it's probably time to rebuild them anyway.

JadeRunner - these gears were setup several years ago, actually by Robbie, and have been broken in for some time. I do not know if simply swapping a third requires extra break-in, but I thought break-in was in reference to the ring and pinion gears actually meshing together nicely for good contact. Am I wrong, and do I need to allow extra time for more break-in?

Thanks for the suggestions everybody. I'm going to get the truck tomorrow as I can't drive my 40 in the increasingly bad weather, and I'll have to tolerate the gear whine until I figure it out. I will keep everyone posted, and thanks again... you guys are truly awesome.

AxleIke
11-15-2009, 02:15 PM
I'm getting re energized to find the issue with mine, and maybe help JJ figure his out too.

So, I went down and checked phase on the rear shaft. It is exactly 90 deg. Meaning that the flange on the driveshaft connected to the transfer case is 90 degrees from the flange on the drive shaft connected to the diff. Can someone confirm that this is correct for a CV style (double cardan) drive shaft?

I also jacked the truck up and checked Ujoints and the driveshaft in general. I found no noticeable play in the u-joints, but I did in the shaft itself.

Its not a lot, but I get some (maybe a 16th of an inch) of play where the splined section is. I never noticed it before, but if I hold the flange on the diff, I can easily move the other part of the shaft. What say ye?

AxleIke
11-15-2009, 09:57 PM
Bump

jjhancock
11-16-2009, 10:52 AM
Picked up the truck yesterday morning. The good news is that I'm loving the 4.88's with my nitto 315's. The bad news is that I'm still getting the strange noises. Didn't have time to work on the truck yesterday as I took the girlfriend to see Wicked for her birthday. I will be confirming the drive shaft in / out of phase this evening and am hoping to rule that out.

AxleIke - can we meet up this week or weekend to compare the noises we're getting after the new gears? I'm curious if the sounds we're concerned about are the same, and if not, how close they might be.

Bobzooki
11-16-2009, 12:08 PM
I suggest a good quality stereo with a high-power amp, turned up to the point that eggs become hard-boiled in front of the speakers in less than 15 minutes. Dig back to the 70's for some Uriah Heep or something, and you'll never know that you have a whine in your diff.

AxleIke
11-16-2009, 12:23 PM
Picked up the truck yesterday morning. The good news is that I'm loving the 4.88's with my nitto 315's. The bad news is that I'm still getting the strange noises. Didn't have time to work on the truck yesterday as I took the girlfriend to see Wicked for her birthday. I will be confirming the drive shaft in / out of phase this evening and am hoping to rule that out.

AxleIke - can we meet up this week or weekend to compare the noises we're getting after the new gears? I'm curious if the sounds we're concerned about are the same, and if not, how close they might be.

Sure thing. Love to meet up.

I talked with Jerry @BT this morning. He's thinking it could be a diff issue.

I found out after searching that you have to check u-joints with a prybar, not just by hand. I'm going to check that this week.

jjhancock
11-23-2009, 09:06 AM
So I pulled the front drive shaft yesterday and attempted to replace the u-joints... I swung the hammer for 2 hours and never got one cup pressed completely out. What a PITA!!! The truck is quieter now with the CDL locked and obviously in rear wheel drive only now, which points to something in the front end. I'm getting the u-joints replaced in the front drive shaft tomorrow which I really hope fixes the problem. If not, then I'm going to have to find some "ears" to isolate the problem and eliminate it.

Anybody know how to pull the cup out of a u-joint, or do I just need WAY bigger vice grips??

AxleIke
11-23-2009, 10:48 AM
I'm sure you did, but you removed the snap rings, right?

I've always assumed that you had to use a press or special U-joint tool for these.

jjhancock
11-23-2009, 12:12 PM
I did get the c-clip / snap rings out, and to be honest that was quite easy. I have decided however, that changing a u-joint is a job best suited for the pros.

I think with the right equipment I would have been fine. I do have one of those press tools that I got from harbor freight a long time ago, and it *seems* like it would work, but it was cumbersome to use to say the least.

jjhancock
11-25-2009, 03:00 PM
Front drive shaft rebuilt and re-installed... same noise. I did a test last night where I drove up and down S. Boulder hill on 36, and although much quieter, the noise I'm hearing is still faintly there when I bump the transmission into neutral going 70 mph downhill. First bet is it's a wheel bearing, 2nd bed is it's the pinion, third bet is the transfer case output bearing. I'm 99% positive the noise is coming from the front... Robbie, did you get your ears yet???

Nay
11-28-2009, 06:00 PM
Ok, you said same noise but quieter? That's probably not your R&P.

Remember that 4.88's make everything spin faster, and old joints on a lift (running at high angle) don't like this.

A decel vibe could very well be your rear driveshaft, either the u-joints on just a "getting pretty old" spline.

I added less than an inch of lift this year and my rear driveshaft hates it. I even lengthened my LCA's to fix the pinion angle and I still get a nice decel vibe. I need new u-joints, maybe an entire new driveshaft.

If your swapped R&P was running smooth before the swap, I'd be looking at the driveshafts and what they connect to - it's amazing what changing the RPM on a well worn pattern can do as far as noise, having lived with drivetrain noise on another rig that drove me insane I feel for you. It was one reason I was very hesitant to ever regear my 80, but Toyota stuff is so good a properly set up 3rd is unlikely to make noise past the break-in period.

Pull the rear driveshaft and leave the front on and see what happens.

AxleIke
11-28-2009, 09:56 PM
I'm working on my rear driveshaft right now. Got the ujoint replaced yesterday, and the double cardan torn down today.

Then, for fun, I cleaned all the grease and paint off with a wire wheel and acetone.

I've also decided to replace my centering joint in addition to both u joints, and I also did the CV high angle modification to get maximum flex out of the double cardan.

It'll be a few days before I get the centering joint, so I won't have results for a while.