Hi!

I'm new here, but I belong to a couple of other auto bulletin boards, so hopefully I won't make a fool of myself in my first post!

We've had older Volvo's in our family forever (well, back to 1965 when my Dad bought his '65 P1800s - which he still has!) and I used to help Dad cup up 444's & 544's back in the late 1960's to build into race cars. We won a lot!

So I'm not a novice when it comes to cars or Volvo's.

I recently purchased a 1964 PV544 that was converted to a (1975?) B20 engine and automatic transmission back in 1991. The car has accumulated about 105,000 miles since then, so it's just now broken in good!

My problem is with the rear end (differential) gears. Actually two probelms: first, the ring and pinion gears were not set up correctly when they were last overhauled, and the lash offset has ruined the faces of the gear teeth. You can hardly hear the engine over the rearend whine. So I need to get a new (or at least good) set of gears.

The second part of the problem is that the builder retained the 4.11:1 gear ratio, which was OK when driving in San Francisco, but not good out here in the flat desert. So what I really need to locate is a good set of gears in a higher ratio - say 3.7-something or 3.55:1.

Now, provided I can locate said gears, does anyone have any words of advice about installation? My books indicate that they use the shim method of getting the clearances and lash set. I've done that once and it worked OK, and I've done lots of GM rearends, which use big rotating nuts as adjusters.

Any help I can get - either locating gears (or at least finding that 3.7-something ratio that I've forgotten!) or an entire rear axle assembly or detailed advice on disassembly/reassembly, or interchange information, I'd really appreciate it.

Steve
Southern California

3.73 was(is?) available for the Dana 27; look around.
I'm pretty sure no Volvos came with one, but Jeep, AMC, and possibly others, used the same differentials.
--
Jim McDonald

That's what I thought. I need some information from someone with an interchange manual. No one around here has one for these early cars.

I have Jeep parts, but the ratio is 5.05 so that's even worse. I can open up a differential and visually compare it to the Volvo, I guess. I'll go talk to the guy who bought my Dad's 544 race car. He stopped racing, but his son says he's got a shed full of parts. Maybe some gear sets?

If he's interested in getting rid of the parts I'll see about hauling them home so we can share...

I'm pretty sure there's 1(one) ring gear, 41 teeth, and 3 pinions, 9(4.56), 10(4.10) and 11(3.73).
The local rear end shop claims they can get Dana 27 parts fairly easily.
--
Jim McDonald

McDuck- I think you may be confused on fitment- just because the teeth count is the same doesn't mean they are the same size teeth- nothing interchages except in original sets.
In general, in term of Volvo ratios,
5.38 is 43/8
4.88 is 39/8
4.56 is 41/9
4.30 is 43/10
4.10 is 41/10
3.91 is 43/11
3.73 is 41/11
3.55 is 39/11
3.54 is 46/13
3.31 is 43/13
3.15 is 41/13
3.08 is 40/13

There are many other combos of teeth counts, Dana may have made more than shown

I have a set of 3.31 that were run dry of oil. I think they might be salvageable. I got my replacements from Walcks 4 wheel drive (internet search will find them). I do know 3.31 & 3.73 type 27 were, long ago, plentiful. Also 3.08 were made, and I think 3.54. I think 3.73 are a waste of time. I would seek 3.31, but I would most likely change rear axles entirely, if I were to do it again. Mopar 8.25 or Ford 8", most likely. Right bolt pattern, and width.

I don't seem to be the one who's confused.
--
Jim McDonald

You imply that one ring gear could be matched with several different pinions, and that that was how the ratios differed. That's how I read it, anyway, and noting your phrase "I'm pretty sure", I didn't think you'd be touchy about it.

To try to word my comment a different way- you couldn't "leave" the ring on and put in another pinion. Neither the thickness of the ring nor the size of teeth have any similarity from on ratio set to another. In fact, it's *very* unwise to attempt to mix even new unworn rings and pinions of the same ratio. I suppose given your record of good replies, you probably know that too.

I've spend ~$2700 CDN with people who *thought* they knew differentials, installing my 3.31's several times on each set I bought. This eventually forced me to learn a lot on my own, so you could say I'm touchy about the subject.

OK, now I seem to have the basic information I needed.

I have been told that the Volvo used a Spicer/Dana 22 differential.

Now I need to find the Dana 27 gears in the correct ratio. I think I'll use the 3.54's. The car is heavy for its' size and it's only a 2-liter engine. I'd love to be able to use the 3.08 set, but I think I'd be underpowered.

I still will drive in the mountains a lot, so I'll compromise between 4.11 (too low) and 3.08 (too high.)

Now...since I'll be re-using my carrier, the number of splines on the axle won't matter.

Thanks for the info. I'll keep you posted and collect pictures as the job progresses.

Steve